"4V 3‘ ' Jul Lv' ui-l’ Valnnfiiq‘x 4% ‘1 L"). , ‘1'.“t i. 31. fl. ' a a? ianfi. z 2 3.. Ag! c .- A v {.r‘ z. .1: .2! 8. 3V 33% 2 VS! a fixrg¢ if .5: a 5' t :17 . £84 39.. V '. .1.“ .. 5.3“ fill... .lva «mud v. .4“... Lb» . c...:x....1.«...!\Nn.... . ,. .r.....i.?. 2 i c a .1 3t. . w ‘ 1 V. ‘11,.‘5‘ l. h r11 ulhnd~d|\.t.o \N\ V . . ..:.u.«.nh.k§w . V , V . . I .B ) v V . ‘ . .. . V. V .a._ i :— , ban . hum)“: . ”uni! {TL V V V n3: Wears Mlcmem STATE LIBRARY lit/Ill!!! N I’ Will?” ll lll’lll/IHII/ll Michigan State 1 university 3 1293 01766 8207 This is to certify that the thesis entitled A SYSTEM'S MODEL FOR A SPARK-IGNITED INTERNAL COMBUSTION ENGINE presented by Yves H.H. Billet has been accepted towards fulfillment of the requirements for Masters..— degree in Mechanical Engineering Date /2//9’/98 0-7639 MS U is an Affirmative Action/Equal Opportunity Institution l". PLACE IN RETURN BOX to remove this checkout from your record. TO AVOID FINES return on or before date due. MAY BE RECALLED with earlier due date if requested. DATE DUE DATE DUE DATE DUE 1M campus-m4 A SYSTEM'S MODEL FOR A SPARK-IGNITED INTERNAL COMBUSTION ENGINE By Yves H.H. Billet A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Mechanical Engineering 1998 ABSTRACT A SYSTEM’S MODEL FOR A SPARK-IGNITED INTERNAL COMBUSTION ENGINE By Yves H.H. Billet Engine-dynamometer tests provide model data necessary for an engine control system to be established. More specifically, dynamometer tests deliver quantitative relationships between control actions (engine control inputs) and engine performance (engine output). For a spark-ignited, port fuel injected internal combustion engine this document describes a system’s framework for the engine subsystems and their signal or power interactions. Steady-state mean value input-output relations for the different subsystems are derived based on dynamometer test data. Engine model control inputs are throttle angle, idle air control, fuel injector pulse width and spark advance. Engine model output performance is formulated in terms of net mechanical power or specific fuel consumption. Experimental procedures are proposed or references provided to obtain all model relations stated. To my parents ACKNOWLEDGMENTS I am very grateful in the first place to my faculty advisor Dr Radcliffe for the full and unconditional support he gave me throughout my education at MSU and during the two thesis projects we ran together. Especially, I would like to thank him for the patience he showed in defining the subject of this thesis and for the backup he gave me in the contacts with other faculty members. Dr Radcliffe, I will always keep in mind the talks we had and the way you responded to the issues I brought up. I have learned more from you than I could ever have hoped to pick up at a university. I would like to thank Dr Schock for accepting my project at the Hulett Road Engine Research Facility and for supplying the space and equipment necessary to set up a test bed for engine control. I would also like to thank Dr Salam and the NSF group in general for long term support of my research and education. Special thanks as well to Dr Shaw and Dr Khalil for being understanding towards my position as a teaching assistant, especially during my last semester at MSU. I am convinced that through their amazing efforts, the NSF course is now put on the right track. Dr Khalil and Dr Shaw, I don’t recall you having caused any of my after-meeting headaches: thanks for being the quiet guys! Of course I reserve a special paragraph for my “older brother and battery specialist” Tom Stuecken, who led me through the experimental work and who taught me how to stand the pain of real-life grease monkey trouble-shooting. Tom, very little at Hulett would be possible without you being around! Thanks for all the time and effort you put into my project! I am very pleased with the research environment at Hulett Road and its people: Mark, thanks for speeding up the contacts with Ford, your once in a lifetime mass airflow sensor discovery and your never ending burger-mania. Dr Brereton, Hans and Dr Lee, thanks for your interest, daily advice and comments. Rahi, Mischa, Steve it was a lot of fun and everyday irony to have you around! Thanks as well to Mr. Milz at Cosworth Engineering and Mr. Lorusso at Ford to supply the information necessary to run the engine controller. Besides, I would like to mention my great companions of the Dynamic Systems Laboratory: Mark, Charles, Byam, Yoga, Joe, Brennan and Gary, you filled my days and nights at the EB with joy and at times very unpredictable madness! The department secretaries Nancy, Carol, Martha, Aida and Bobby deserve a special note for their everyday enthusiasm and support in administrative matters. Finally, I would like to express my greatest appreciation towards my international friends at MSU. Lars, Thomas, Ramez, Khash, Laurel, Jim, Bernhard, Kara, Fariba, Taka, Nao, Azu, Takeo, Su, Dae Yong and Natalie: I will never forget the time we spent together! Thank you very very much!! TABLE OF CONTENTS LIST OF TABLES. ................................................................................................ ix LIST OF FIGURES ................................................................................................ x KEY TO SYMBOLS OR ABBREVIATIONS ....................................................... xiii INTRODUCTION ................................................................................................... 1 CHAPTER 1 MECHANICAL SYSTEMS INTERACTION ........................................................... 4 CHAPTER 2 INDICATED WORK AND INDICATED FUEL CONVERSION EFFICIENCY ....... 12 CHAPTER 3 FUEL INJECTION SYSTEM ............................................................................... 18 CHAPTER 4 AIR INTAKE SYSTEM ........................................................................................ 26 CONCLUSION .................................................................................................... 30 APPENDIX A ENGINE-DYNAMOMETER SETUP .................................................................... 34 A.1 Dynamometer Specifications ................................................................ 34 A.1.1 General Electric DC Electric Dynamometer ............................... 34 A.1.2 Load Cell (south side) ............................................................... 34 A.1.3 Variable Reluctance Speed Sensor ........................................... 35 A2 Dynamometer Sensor and Actuator Calibration .................................... 35 A.2.1 Load Cell/Torque Display Calibration ........................................ 35 A22 Dynamometer RPM Display Calibration .................................... 36 A23 Dynamometer Throttle Actuator ................................................. 36 A.2.4 Dynamometer Throttle Position Display Calibration ................... 38 A.3 Engine-Dynamometer Coupling Design ................................................ 38 A4 Engine Specifications ........................................................................... 41 A.4.1 Engine Block .............................................................................. 41 A42 Engine Cooling System ............................................................. 41 A.4.3 Fuel System ............................................................................... 41 A.4.4 Ignition System .......................................................................... 42 A5 Engine Bracket Design ......................................................................... 42 A51 Front Bracket Base Plate ........................................................... 43 A.5.2 Front Bracket U-Profile Bridge ................................................... 43 A53 Rear Support Pillar Mounting Plate ............................................ 45 vi A.6 Engine Alignment .................................................................................. 47 A.7 Engine Cooling System ........................................................................ 48 A.7.1 Heat Exchanger Switching between Two Engines ..................... 49 A72 Coolant Draining Procedure ...................................................... 50 A.7.3 Coolant Refill Procedure ............................................................ 50 A.7.4 Operating Conditions ................................................................. 51 A8 Exhaust System .................................................................................... 52 A81 Fan Specifications ..................................................................... 52 A82 Heat Shielding ........................................................................... 52 APPENDIX B DYNAMOMETER OPERATION .......................................................................... 54 B.1 Safety Checks ..................................................................................... 54 3.1.1 Fire Safety ................................................................................. 54 B12 Mechanical Safety ..................................................................... 55 B.2 Pre-run Check and Running Preparation ............................................. 55 B.3 Dynamometer Startup ......................................................................... 56 B.4 Dynamometer Control System ............................................................ 63 8.4.1 Control Display .......................................................................... 63 3.4.2 External Feedback Control Mode .............................................. 63 8.4.3 Position/Excitation Control Mode ............................................... 64 8.4.4 Loading the Engine in “XFB” Mode ............................................ 65 3.4.5 Loading the Engine in “PIE” Mode (measurement of Torque- speed curves) ............................................................................ 66 B.5 Dynamometer Shutdown ..................................................................... 67 APPENDIX 0 ENGINE OPERATION USING THE ELECTRONIC ENGINE CONTROL MODULE FROM FORD ...................................................................................... 69 0.1 Functional Overview ............................................................................ 69 0.2 Sensors ............................................................................................... 70 0.2.1 Crankshaft Position Sensor (Fig. 0.1) ....................................... 70 0.2.2 Camshaft Position Sensor (Fig. 0.2) ......................................... 71 0.2.3 Throttle Position Sensor (Fig. 0.3) ............................................ 72 0.2.4 Mass Airflow Sensor (Fig. 0.5) .................................................. 74 0.2.5 HEGO Sensor (Fig. 0.7) ............................................................ 76 0.2.6 Air Charge Temperature (ACT) Sensor ..................................... 78 0.2.7 Engine Coolant Temperature (ECT) Sensor (Fig. 0.11) ............ 79 0.3 Actuators ............................................................................................. 81 0.3.1 Fuel Injectors ............................................................................. 81 0.3.2 Idle Air Control (IAC) Valve (Fig. 0.13) ...................................... 82 0.4 Operator Panel Wiring Diagram and Emergency Switching ................ 83 0.4.1 Switching Electronics and Relays .............................................. 83 0.4.2 Other Operator Panel Manual Switches .................................... 88 0.4.3 Analog Display Devices ............................................................. 89 0.4.4 Wiring to the EEC, the EDIS and the Sensors ........................... 90 vii CI I. 0.5 Breakout Box and Control Signal Monitoring ....................................... 91 0.5.1 Breakout Box Pinout Chart ........................................................ 91 0.5.2 Control Signal Monitoring .......................................................... 92 0.5.3 Measuring Spark Advance ........................................................ 93 0.5.4 Measuring Injection Timing ........................................................ 94 0.6 Control System Operation and Mapping ............................................. 94 0.6.1 Base Spark and Fuel Maps in Terms of Throttle Angle ............. 95 0.6.2 Discussion of the Base Timing .................................................. 96 0.6.3 Map Boundaries and Blanks ...................................................... 99 0.6.4 Base Spark and Fuel Maps in Terms of Manifold Pressure and Cylinder Air Charge ................................................................. 100 0.6.5 Cold Start Enrichment ............................................................. 103 0.6.6 Air Charge Temperature Trimming of Fuel Injection ................ 105 0.6.7 HEGO Trimming of Fuel Injection ............................................ 106 0.7 Engine Startup and Shutdown Procedures ....................................... 108 0.7.1 Engine Startup (using the Ford EEC) ...................................... 108 0.7.2 Engine Shutdown .................................................................... 109 0.8 Remaining Tasks .............................................................................. 109 APPENDIX D MAIN DOCUMENT DATA SHEETS .................................................................. 111 REFERENCES .................................................................................................. 119 viii TTITITITITITITTI Ti .I.T.IT._I.IT. LIST OF TABLES Table A.1: Dynamometer RPM Display Calibration Table A2: Dynamometer Throttle Position Display Calibration Table B.1: Dynamometer Startup Sequence Table B.2: Dynamometer Shutdown Sequence Table 0.1: Mass Airflow Calibration (Sensor FOCF-12B579-A) Table 0.2: ACT Sensor Calibration (Sensor F22F-12A697-AA) Table 0.3: ECT Sensor Calibration (Sensor E4AF-12A848-AA) Table 0.4: EEC Breakout Box Pinout Chart Table 0.5: Spark Advance = f (RPM,6) Table 0.6: Fuel Flow Rate = f (RPM,6) Table 0.7: Injector PW= f (RPM, 9) [FOSE-9F593-A1A only] Table 0.8: Manifold Pressure pm = f (RPM, 9) Table 0.9: Mass Airflow rita = f (RPM,0) Table 0.10: Cold Start Multiplier as a Function of Block Temperature Table 0.11: Relative A/F Ratio 1 = (A/F)/(A/F)sioicn as related to HEGO Feedback Table D1: Friction Torque = flRPMfl), refer to Fig.6 Table D2: Gross Indicated Torque = KRPM,9), refer to Fig.7, (@ 97.1 kPa, 24.5°C) Table D3: Mechanical Efficiency = l(RPM,0), refer to Fig.8 Table D4: SAI Multiplier, refer to Fig.9 (SA-MBT in ° crank) Table D5: AFI Multiplier, refer to Fig.10 Table D6: In-Cylinder Fuel Mass, refer to Fig.13 Table D7: Indicated Fuel Conversion Efficiency = f(RPM,6), refer to Fig.14 Table D8: In-Cylinder Fuel Mass at Stoechiometry, refer to Fig.15 Table D9: Cylinder Air Charge, refer to Fig.17 Table D.10: Calculated MBT = KRPMfl), refer to Fig.18 Table D.11: Stoichiometric Fuel Conversion Efficiency = f(RPM,6), refer to Fig.19 Table D.12: Cylinder Air Charge = f(RPM, pm), refer to Fig.22 LIST OF FIGURES Fig.1: Overview of the Facility (Construction Stage) Fig.2: Schematic of the Facility Fig.3: Overall Model Structure Fig.4: Engine-Dynamometer Mechanical Power Flow Fig.5: Mechanical Systems Power and Signal Interaction Fig.6: Measured Friction Torque Tf, 1995 1.9 liter Ford Escort Fig.7: Gross Indicated Torque Ti, 1995 1.9 liter Ford Escort, using (4) Fig.8: Mechanical Efficiency, 1995 1.9 liter Ford Escort, using (8) Fig.9: SAI Multiplier, 1995 1.9 liter Ford Escort, using (20) Fig.10: Fig.11: Fig.12: Fig.13: Fig.14: Fig.15: Fig.16: Fig.17: Fig.18: Fig.19: Fig.20: Fig.21: Fig.22: AFI Multiplier, 1995 1.9 liter Ford Escort, using (21) Port Fuel Injection System Fuel Injector Calibration, 1995 liter Ford Escort, using (25) Measurement of the In-cylinder Fuel Mass mic, 1995 1.9 liter Ford Escort Indicated Fuel Conversion Efficiency, 1995 1.9 liter Ford Escort, using(13) Measurement of the In-cylinder Fuel Mass at Stoichiometry, 1995 1.9 liter Ford Escort (stoichiometry was estimated using the signal from the HEGO) Relative Air to Fuel Ratio A , 1995 1.9 liter Ford Escort, using (23) Cylinder Air Charge mac, 1995 Ford Escort 1.9 liter, using (26) Calculated MBT using Fig.17 and Mapping Data on the 1990 Ford Escort 1.9 liter obtained from Ford Motor Co. Stoichiometric Fuel Conversion Efficiency at MBT, 1995 1.9 liter Ford Escort, using (19) and the curve fits of Fig.9 and Fig.10 Induction System Signal Flow Measured Mean Manifold Pressure, 1995 1.9 liter Ford Escort without Air Filter, pa: 97.1 kPa, To = 24.5 °C Cylinder Air Charge, 1.9 Iiter1995 Ford Escort, using Fig.17 and Fig.21 Fig. A.1: Dynamometer RPM Calibration Fig. A.2: Throttle Actuator Fig. A.3: Dynamometer Throttle Position Calibration Fig. A.4: Angular and Parallel Coupling Misalignment rhl furl FIF F 1H. F F F F F F F III I, I. I III III III III III Fig. A.5: Engine-Dynamometer Coupling Fig. A.6: Front Bracket Base Plate Fig. A.7: Front Bracket Bridge and U-profile Fig. A.8: Engine Front Bracket Mounting Fig. A.9: Rear Support Pillar Mounting Plate Fig. A.10: Rear Support Plate Bending Fig. A.11: Engine Rear Support Pillar Mounting Fig. A.12: Bridge with Pulley for Engine Alignment Fig. A.13: Coolant Valve System Fig. A.14: Coolant Reservoir Fig. A.15: Exhaust Fan Fig. 8.1: Dynamometer DC Drive Fig. B.2: Dynamometer Control Panel Fig. 83: Dynamometer DC Drive Display Location Fig. 0.1: Crankshaft Position Sensor Fig. 0.2: Camshaft Position Sensor (Located behind the Intake Manifold) Fig. 0.3: Throttle Position Sensor Fig. 0.4: TPS Resistance Fig. 0.5: Mass Airflow Sensor Fig. 0.6: Mass Airflow Calibration (Sensor FOCF-12B579-A) Fig. 0.7: HEGO Sensor Fig. 0.8: HEGO Sensor Terminal Identification Fig. 0.9: Air Charge Temperature Sensor Fig. 0.10: ACT Sensor Calibration (Sensor F2ZF-12A697-AA) Fig. 0.11: ECT Sensor Calibration (Sensor E4AF-12A848-AA) Fig. 0.12: Flow Bench Test Results for Gray Body FOSE-9F593-A1A Fuel Injectors Fig. 0.13: Idle Air Control Valve Fig. 0.14: Front of the Operator Panel Fig. 0.15: Switching Scheme for Power Supply to the Engine Electrical Subsystems Fig. 0.16: Operator Panel Switching Operation Fig. 0.17: Ford Controller Breakout Box xi ’11—‘11 Fig. 0.18: Base Spark Advance Map Fig. 0.19: Base Fuel Flow Rate Map Fig. 0.20: Manifold Pressure @ p0: 96.3 kPa, To = 24.5 °C Fig. 0.21: Mass Airflow @ po= 96.3 kPa, To = 24.5 °C xii m m“ "I KEY TO SYMBOLS OR ABBREVIATIONS ACT: Air Charge Temperature AFI: Air Fuel Ratio Influence Function [] dulylAc: Idle Air Control Valve Duty cycle [%] ECT: Engine Coolant Temperature EDIS: Electronic Distributorless Ignition System EEC: Electronic Engine Control Module EGO: Exhaust Gas Oxygen Sensor EGR: Exhaust Gas Recirculation FB: Feedback G : Fuel Injector Flow Conductance [(m3/s)/Pa”2] HEGO: Heated Exhaust Gas Oxygen Sensor IAC: Idle Air Control LED: Light Emitting Diode n't: MAF Sensor Airflow [kg/hr] ma : Mass Airflow [kg/hr] mac : Cylinder Air Charge [kg] "'20,: Mass Airflow into the Intake Manifold [kg/s] n'zao: Mass Airflow out of the Intake Manifold [kg/s] n‘z, : Fuel Flow Rate [kg/hr] mfc : Cylinder Fuel Mass [kg] (mfc)s,o;ch: Cylinder Fuel Mass at Stoichiometry [kg] n'tfit Fuel Injector Mass Flow Rate [kg/hr] n: number of cylinders m: number of the spark plug in the firing sequence MAF: Mass Airflow MBT: Minimum Spark Advance for Best Timing [deg crank BTDC compression] offset: Fuel Injector Offset [ms] p: Pressure [Pa] Pb : Engine-Dynamometer Power Transfer [Nm/s] xiii Sf: n. «U T.- T. T TF PIE: Position/Excitation pf: Pressure Upstream of the Fuel Injector [Pa] Pf: Mechanical Loss Power [Nm/s] P1: Gross Indicated Power [Nm/s] pm: Manifold Pressure [Pa] PM: Net Available Mechanical Power [Nm/s] pa: Environmental Pressure [Pa] PWE injector pulse width [ms] 0: Volumetric Flow [ma/s] Of: Volumetric Fuel Flow into the Intake Runner [ma/s] Om: Lower Heating Value of the Fuel = 44.0 MJ/kg 050: Fuel Injector Volumetric Flow [ma/s] r: Ideal Gas Constant of Air = 287 J/(kg K) RACT: ACT Sensor Resistance [kn] R507: ECT Sensor Resistance [kn] RHEGO' HEGO Heating Resistance [(2] RPM Engine speed [rot/min] Rrps: Throttle Position Sensor Resistance [kn] SA: Spark Advance [DBTDC compression] SAI: Spark Advance Influence Function [] SP: Set Point sfc: Specific Fuel Consumption [mg/Nm or (g/s)/kW] T: Torque [Nm] TAcr: Air Charge Temperature [°C] Tb: Brake Torque [Nm] Twas: Desired Dynamometer Load Torque [Nm] Tm: engine block temperature [K] T501: Engine Coolant Temperature [°C] T;: Gross Indicated Torque [Nm] Tm: manifold temperature [K] To: Environmental Temperature [K] TPS: Throttle Position Sensor xiv Vc: Displaced Cylinder Volume [m3] Vren Mass Airflow Sensor Supply Voltage [volt] Wedge]: Actual Work available Mechanically over a Combustion Event [Nm] Ill/ideal: Ideal Work available Thermally over a Combustion Event [Nm] WOT: Wide Open Throttle XFB: External Feedback 17,: Indicated Fuel Conversion Efficiency [] mjsmh: Stoichiometric Fuel Efficiency [] 17”,: Mechanical Efficiency [] 0 : Throttle Angle [deg] 6 ’: Dimensionless Throttle [] 9 wort Throttle Angle at Wide Open Throttle [deg], 88.9 9 A : Relative Air to Fuel Ratio = (A/F)/(A/F)smic.1 p,: Fuel Density [kg/m3] a): Angular Velocity [rad/s] (Odes: Desired Dynamometer Angular Speed [rad/s] we: Crankshaft Angular Velocity [rad/s] cog: Dimensionless Engine Speed mm: Nominal Engine Speed [rad/s], 4500 RPM INTRODUCTION Government mileage and emission regulations for spark-ignited combustion engines have left automotive engineers with a complicated optimization task [Ribbens, 1998]. Most automobile engine inventions date from the first half of the 20th century. Long-term experience has led to continuous and extensive design optimization of mechanical and electrical subsystems [Hempson, 1976, Heywood, 1988]. Research and testing efforts associated with incremental changes in engine performance through design adjustments have however grown tremendously. Systems and controls engineers take an alternative, active, route in the optimization process. The idea is to allow for engine design limitations but to compensate for these by steering the engine into optimal performance by means of feedback controlled engine operation. Control actions are taken based on engine modeling information and on-Iine measurements. Control models typically covers the physical behavior and interaction of the engine subsystems. Powell (1987), Powell and Cook (1983), Huang and Velinsky (1993) give an extensive overview of the field of spark-ignited engine modeling for application in electronic engine control. Model information is commonly extracted from engine-dynamometer test data ['Iennant, Giacomazzi, 1979]. This document describes a system’s framework to establish the functional relationships between control inputs and engine output performance. Engine control inputs are: idle air control (IAC), throttle, fuel injection timing and ignition timing. Performance is formulated in terms of mechanical power or specific fuel consumption and related to measurable quantities in an engine-dynamometer test. An engine-dynamometer test bed was constructed to provide model data. Tests were run on the 1995 1.9 liter Ford Escort driven by its own electronic engine control module. Tests requiring changes in spark or fuel injection timing were conducted using the Cosworth Intelligent Controls |05460 Engine Control System ®. Fig. 1: Overview of the Facility (Construction Stage) The facility (Fig.1) consisted of a bi-directional D0 dynamometer and dynamometer control system, which could quickly switch operation between the Ford Escort engine and a research engine for the Environmental Protection Agency. The Cosworth |05460 Engine Control System ® was shared between the two engines (Fig.2). Test results are discussed in the main document. The appendices contain details on operation of the facility and listing of test data. 0 {-5 r f EPA Engine —| H Dynamometer —| I—[Ford Escort Engine Ignition & Dyno Controls nil-QB; Fuel Injection 7 Sensors T l I A Ignition & Y 4 Fuel injection Cosworth Control S stem 7—- y d——-I P0 _. Fig.2: Schematic of the Facility SU dy Chapter 1 MECHANICAL SYSTEMS INTERACTION The control model relationships between engine output performance and engine control inputs are derived in several steps. The engine is subdivided Into a set of interacting subsystems of lesser size and model complexity. The subsystems are subsequently characterized through dynamometer measurements. This is done in an ordered manner, starting with the output side of the engine (engine performance) and working back to the input side (control inputs). Steady engine operation is considered only: the engine is not accelerating. All model relations are formulated in terms of mean quantities over time. Throttle Angle, 0 . Idle Air Duty Cycle, dufylAc—b En glne Spark Advance, SA —p Fuel Injector Pulse Width, PW—p MOdel H Net Output Power, PM, —-> Specific Fuel Consumption, sfc Fig.3: Overall Model Structure The overall model structure (Fig.3) has the following inputs: throttle angle (6), idle air control valve duty cycle (dutylAc), spark advance (SA) and fuel injector pulse width (PW). The model outputs are the net mechanical engine power PM and the specific fuel consumption sfc. The engine-dynamometer mechanical power flow (Fig.4) is driven by the gross indicated power (P,). The gross indicated power is distributed over three subsystems: the mechanical dynamics, the mechanical losses (P;) and the dynamometer (Pb). The dynamometer brake power Pb represents the power transfer to the dynamometer through the engine-dynamometer shaft coupling. An electrical dynamometer can both absorb power (generator mode) and supply power (motor mode). We will assume Pb is positive when flowing into the dynamometer. If the engine overcomes its mechanical losses when firing, the direction of the power transfer Pb depends on whether engine ignition is activated or not. Indicated P, Mechanical Work ' Dynamics _l—p Dynamometer Mechanical Losses ENGINE Fig.4: Engine-Dynamometer Mechanical Power Flow The mechanical loss power P; accounts for friction losses and also includes the pumping work of the engine during intake and exhaust strokes. pmj Indicated —T’p Mechanical —‘i’°—u Dynamometer Work n— Dynamics H—IL— & Dyno l SI. in]... I j 1 Mechanical “’d 9d,, OR Twas Losses we mfc 9—> Fig.5: Mechanical Systems Power and Signal Interaction Mechanical power interactions are expanded into pairs of power variables (torque Tand angular speed co) in Fig.5. The causal relationships indicated by the arrow pairs define which of the power variables are input variables and which are output variables to the separate subsystems. The Mechanical Dynamics have the angular speed we as a kinetic energy storage variable: speed is the natural output variable of the Mechanical Dynamics subsystem. Causality requires all torque interactions to be input variables to the Mechanical Dynamics subsystem. Signal level interaction between subsystems (Fig.5) does not have significant power flow associated with it. Unlike power interactions, signal interactions are represented by single arrows. Kamopp and Margolis (1990) give a discussion of system modeling based on causality, power and signal interactions. We will now develop the relation between input and output variables for the different subsystems. The Dynamometer is a controlled device. The dynamometer control system sets the brake torque Tb as a function of the input variables to the dynamometer control system. The user specifies the desired engine speed codes. In addition, the user is given control over the power interaction between engine and dynamometer by setting the power produced by the engine or by setting the power absorbed by the dynamometer. Control over the power produced by the engine is given by means of the throttle angle 0. Control over the power absorbed by the dynamometer is given by means of the brake torque Tb. The user then specifies either a desired throttle angle Bees or a desired brake torque dees - The dynamometer control system measures the shaft rotational speed we and compares this speed to the desired value wees. In the control mode of specified throttle angle (Bees), the dynamometer control system sets the throttle angle at the user-specified value Bees and adjusts the brake torque Te until the speed error becomes zero. In the control mode of specified load torque (Tedee), the dynamometer control system sets the brake torque Te at the user-specified value Teeee and adjusts the throttle angle 6 until the speed error becomes zero. If even at wide-open throttle (WOT) the engine cannot generate the specified brake torque Teeee, the dynamometer will fully open the throttle and reduce the brake torque to a value lower than the specified value Teeee. The Mechanical Losses block has the friction torque T; as an output variable and crankshaft angular velocity we and throttle angle 9 as input variables. A functional relationship of the form T, =f,(0,w,) (1) is proposed. Dependency on engine speed accounts for viscous friction as well as for the variation of the pumping losses with engine speed. Dependency on throttle angle accounts for the variation of the pumping losses in the intake system with the throttle position. Effects not included in the model are other quantities influencing friction, such as pressure inside the cylinder and valvetrain loading. The model assumes that piston ring friction and valvetrain loading are not significantly different under variations in cylinder pressure. The Indicated Work block represents the mechanical power production from the combustion process. It has the gross indicated torque (T,-) as an output variable and crankshaft angular velocity (we), mean manifold pressure (pm), cylinder fuel mass (mic), relative air to fuel ratio (A) and spark advance (SA) as input variables. At steady operation we propose a functional relationship of the form 7:- = f: (me. p..w.,l. SA) (2) The gross indicated torque also depends on other quantities such as heat transfer and exhaust gas recirculation. We will however only study the influence of the quantities given in (2). At steady operation, the engine is not accelerating and the kinetic energy of the mechanical dynamics is constant: the gross indicated power equals the sum of the loss power and the brake power: P, = Pf + P, (3) Input-output power flows of the Mechanical Dynamics block (Fig.5) all have the same associated speed we. The power conservation (3) can therefor also be expressed in terms of torque: T, = T, + T, (4) A friction torque estimate (Fig.6) was obtained by turning off the ignition (T; = 0) and running dynamometer tests for several throttle conditions Oeee at different speed set points weee. The model estimate assumes that piston ring friction and valvetrain loading are not significantly different In the motored configuration than in the firing configuration. Temperature effects on oil and coolant viscosity were reduced by bringing the engine back to its operating temperature in between a series of measurements. Block temperature was still found to vary between 175°F and 195°F during motoring. Measured friction torque data (Fig.6) are shown as a function of dimensionless throttle (0:6/9wor, Owor = 88.9°) and dimensionless speed (w’: aL/wnem, wee”, = 4500 RPM). 8 8 B 8 Frlctlon Torque 11 [Nm] 21.00 .. , 19.00 ‘ " I 17.00 I 15.00 Fig.6: Measured Friction Torque T;, 1995 1.9 liter Ford Escort The friction torque (Fig.6) predominantly varies linearly with engine speed, indicating viscous effects. For lower throttle angles, the friction increases due to the increased pumping losses in the intake. Quadratic pumping loss dependency on engine speed starts to show at lower throttle angles. The gross indicated torque (T,-) for a firing engine (Fig.7) is obtained by adding the friction torque estimate T;(Fig.6) to the dynamometer brake torque reading (Te). Fig.7 shows calculated gross indicated torque as a function of dimensionless speed (we’) and dimensionless throttle (0’). time Indlceted Torque 11 [Nm] 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Fig. 7: Gross Indicated Torque T,, 1995 1.9 liter Ford Escort, using (4) Engine output performance in terms of net available mechanical output power (PM) or specific fuel consumption (sfc) is directly related to the measured quantities TD and T}. The engine net output power equals the brake power: P... =Pl. =Tl 40. (6) The specific fuel consumption (sfc) as a measure of mileage is inversely proportional to the product of the mechanical efficiency (11,") and the indicated fuel conversion efficiency (1),): 1 =_ 7 sfc "[7“.th ( ) with One the lower heating value of the fuel. Mechanical efficiency (Fig.8) follows from the dynamometer measurements 7'; and T}: T = i = l -- -—— = l — —f 8 11,. T.- ( ) The indicated fuel conversion efficiency relates to the functional properties (2) of the Indicated Work block. It cannot yet be determined based on the torque measurements presented. The additional measurements required to characterize the Indicated Work block are explained in the next section. 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Fig. 8: Mechanical Efficiency, 1995 1.9 liter Ford Escort, using (8) 11 Chapter 2 INDICATED WORK AND INDICATED FUEL CONVERSION EFFICIENCY The Indicated Work block and the indicated fuel conversion efficiency 17, will now be studied in detail to generate an expansion for the gross indicated torque function (2). We will adapt the structure proposed by Dobner (1980) and further expanded by Chang (1988) and Moskwa (1987). Their model for the gross indicated torque function (2) separates the influence of the inputs to the Indicated Work block on torque production based on quasi-physical considerations. The indicated fuel conversion efficiency 1), is the ratio of the energy produced mechanically (Weeeel) to the ideal energy available thermally (VI/ieeeI) over one combustion event: actual (9) The ideal energy available thermally over one combustion event is taken equal to the lower heating value Om, of the fuel times the fuel mass me inside the cylinder: “lideal = th . mfc (10) The actual work produced mechanically over one combustion event equals the gross indicated power P,- divided by the number of combustion events per 12 second. For a four-stroke engine with n cylinders the actual work produced becomes: 47r- P" (11) n-w, W actual — The gross indicated power P) equals the gross indicated torque 7', times the angular speed we, with (11): =4m5 (12) n W actual The indicated fuel conversion can be evaluated with (9), (10), (12): _ 4“. n.we.th'mf C n, (13) A model for the indicated fuel conversion efficiency as a function of the Indicated Work block inputs is presented. As shown by Chang (1988) through combustion simulations, the indicated fuel conversion efficiency can be expanded as the product of a spark advance influence factor SA], a relative air to fuel ratio influence factor AFI and the stoichiometric fuel conversion efficiency mleleieh: 71f: Tlflsroich 'AFI - SA] (14) The stoichiometric fuel conversion efficiency equals the indicated fuel conversion efficiency with the relative air to fuel ratio 1! at stoichiometry (11:1) and the spark advance SA at its Minimum advance for Best Timing (MBT). The stoichiometric fuel conversion efficiency depends on intake conditions (mean manifold pressure pm) and engine speed (we): ansrol'ch=ansmich (pm, we) (15) 13 The SA! and AFI multipliers model efficiency deviations from the reference conditions (SA = MBT, A = 1): AFI = AFI(/1) (16) SA] = SAI(SA — MBT) (17) Through the definitions of AFI and SA! AFI(1)= 1, SAI(0)=1 (18) Calculation of the functions (15), (16) and (17) is done using (13) combined with (14): . (Pew. )- AFI(A)- SAI(SA -MBT)-_- 47‘ 'Tl starch n - we - th . mfc 7?, (19) To characterize the SA! multiplier, it suffices to hold the relative air to fuel ratio (,1), the mean manifold pressure (pm), and the engine speed (we) at arbitrary but fixed values and to measure the variation in gross indicated torque (7')) due to changes in the spark advance (SA) with respect to MBT. The SA! multiplier for the measurements in the above procedure is obtained by dividing (19) through its value at MBT, with (18): SAI(SA - MBT) = T" (20) i ISA=MBT 14 Fig.9: SAI Multiplier, 1995 1.9 liter Ford Escort, using (20) Experimental values and a quadratic least square curve fit for the SA] multiplier are given in Fig.9. The highest value for the efficiency occurs at MBT(SA-MBT: 0). To measure the AFI multiplier, it suffices to hold the spark advance (SA), the mean manifold pressure (pm), and the engine speed (we) at arbitrary but fixed values and to measure the variation in gross indicated torque (Tl) due to changes in the relative air to fuel ratio (A) with respect to stoichiometry. For fixed intake conditions (fixed manifold pressure and air charge), a change in ,1 implies a change in cylinder fuel mass (mfg). The AFI multiplier for the measurements in the above procedure is obtained by dividing (19) through its value at stoichiometry, with (18): (21) 15 Experimental values and a least square polynomial curve fit for the AFI multiplier are given in Fig.10. A sixth order polynomial was required to accurately capture the maximum of the curve and the AFI value of 1 at stoichiometry. The highest efficiency occurs for a slightly lean mixture (II > 1). Calculation of the stoichiometric fuel conversion efficiency is done using (19). The stoichiometric fuel conversion efficiency is mapped for a set of intake (pm) and engine speed (we) conditions at arbitrary A/F ratio and arbitrary SA. At all mapping conditions, A/F ratio and SA are calculated and the SA! and AFI multipliers evaluated using the curve fits of Fig.9 and Fig.10. 1.05 i I I l l I l 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 Relative Air/Fuel Ratio Fig. 10: AFI Multiplier, 1995 1.9 liter Ford Escort, using (21) There are three fundamental problems with this approach to calculation of the stoichiometric fuel conversion efficiency. First, SAI multiplier evaluation is not 16 straightforward because MBTis dependent on both cylinder air charge (mac) and engine speed (we): MBT = MBT(mac,w,) (22) Second, AFI multiplier evaluation is not straightforward because the relative air to fuel ratio A is: (m [c )sroich mf C 2. = (23) with me and (mfc)stoich the actual fuel mass in the cylinder and the fuel mass in the cylinder at stoichiometry. Evaluation of (23) requires measurement of the in- cylinder fuel mass. Finally, mapping of the stoichiometric fuel conversion efficiency using (19), even for known AFI and SA! also requires measurement of the in-cylinder fuel mass mle. Determination of the in-cylinder air charge (mee) and the in cylinder fuel mass (ITIfc) as required for the evaluation of AFI, the evaluation of SA! and the mapping of mleteleh cannot be done through direct measurement. The next section gives a procedure to measure the cylinder fuel mass and a way to estimate the cylinder air charge, as related to the pulse width (PW) command of the fuel injection system. 17 Chapter 3 FUEL INJECTION SYSTEM Fuel Pump/ . gt , Fuel Pressure Regulator/ I Q, _ Injector 4—PW Fuel Tank System ‘ T Pm Oil Intake Fig. 11: Port Fuel Injection System The cylinder fuel mass (mfg) is required for mapping of the stoichiometric fuel conversion efficiency (19) and for evaluation of the AFI multiplier (21). It cannot be measured directly, but it depends on the injector pulse width control (PW) of the fuel injection system (Fig.11). The causal relations between the different fuel injection subsystems are presented in Fig.11. Power flow interactions are formulated through pairs of power variables (pressure p and volumetric flow 0). The pressure regulator controls the pressure p; upstream of the injector based on a pressure signal pm from the intake manifold. The pressure p, is regulated such that the pressure drop Apeee = p, — pm across the fuel injector stays constant. The flow through the fuel injector depends on the pressure drop Ap = p, - pm across the injector. Due to the action of the pressure regulator Ap = Apdes. such that the injector volumetric flow rate becomes: 18 Qio = G ' Apdes (24) The electronic control unit applies a voltage pulse to the fuel injector with pulse width PW. The mass of fuel injected during an injection event is equal to: m [c = (PW - offset)- p f ~Q,o = (PW — 0ffset)-ri1fi (25) p; is the fuel density and (rilfi) the injector mass flow rate. The value offset refers to the opening time of the injector. litigated Mass per mm Event [g1 mfi=6.44kg/hr ’ ‘ "‘ofif‘sét =08“th " " 0 6 1 0 16 Injectoc PW [me] Fig. 12: Fuel Injector Calibration, 1995 1.9 liter Ford Escort, using (25) Measurement of the injector flow rate n'zfi and the injector offset was done in a flow bench test. During the test, an injector is fired a preset number of times with a known pulse width PW. The fuel mass per injection event is recorded by weighting. The mass per injection is plotted versus pulse width (Fig.12) and a linear least square fit is obtained. The injector flow rate depends on the pressure drop (24): during the calibration test, the pressure drop must equal the value Apdes imposed by the pressure regulator in a firing engine. The injector flow rate 111,, is found as the slope of the linear curve. The injector offset is found as the intersection of the linear curve with the PW axis. 19 HM? In-Cyllnder Fuel Meee mfc [kg] 0.00002 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 DImeneIonIeee Speed Fig. 13: Measurement of the In-cylinder Fuel Mass mle, 1995 1.9 liter Ford Escort The in-cylinder fuel mass (Fig.13) for the operating conditions of Fig.7 is determined in a dynamometer test by measurement of the injector PW during steady operation and application of (25). Fig.13 reflects the base fuel settings of the engine control system as a function of dimensionless throttle and dimensionless speed (we'). An average value for the PW was recorded to average out the effect of the exhaust gas oxygen feedback control on the injector pulse width. The indicated fuel conversion efficiency m (Fig.14) can now be determined as a function of dimensionless speed (we') and dimensionless throttle (9 ’) by combining the in-cylinder fuel mass (Fig.13) with the gross indicated torque (Fig.7) through application of (13). 20 0.390 P 3 o 9 w or 0 .° W .e O S 8 Indicated Fuel Conversion Efficiency 9 8 O P M ~l o 0.250 ‘ .. . 0.2 I 0.30.4 0.5 I I 0.6 0.7 0.8 I 0. 1 Dlmenelonleee Speed Fig. 14: Indicated Fuel Conversion Efficiency,1995 1.9 liter Ford Escort, using (13) The in-cylinder fuel mass at stoichiometry (mle)e,eleh (Fig.15) is determined by measurement of the injector PW at stoichiometry and application of (21). Stoichiometric conditions were estimated using the signal from the Heated Exhaust Gas Oxygen (HEGO) sensor. The injector PW was varied until the HEGO sensor started to switch between rich and lean voltage levels. The PW at stoichiometry was taken as the PW for which the HEGO sensor signal on average stays rich and lean for an equal amount of time. The relative air to fuel ratio A (Fig.16) is found out of the measurements of the cylinder fuel mass (Fig.13) and the cylinder fuel mass at stoechiometry (Fig.15) with application of (18). The AFI multiplier at the measurement points of Fig.7 can now be evaluated using the SAI curve fit of Fig.10. 21 0.000023 I 0.000021 0.000019 11 Cylinder Fuel Mass at Stoechiometry [kg] _ 0.000017 ‘ oom15 . r . , ' g, >7 ' ~ . ~ . . - t . 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Dimensionless Speed Fig. 15: Measurement of the ln-Cylinder Fuel Mass at Stoichiometry, 1995 1.9 liter Ford Escort (stoichiometry was estimated using the signal from the HEGO) 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Dlrnenelonleee Speed Fig. 16‘. Relative Air to Fuel Ratio 1., 1995 1.9 liter Ford Escort, using (23) 22 The in-cylinder air charge (mee) (Fig.17) is proportional to the in-cylinder fuel mass (mam at stoichiometry (Fig.15): mac = 14-6 '(mfc).rfoich (26) The minimum spark advance for best timing (MBT) depends on cylinder air charge mee and engine speed we (22). The map (22) was not generated but obtained from Ford timing information on the 1990 1.9 liter Ford Escort. For every air charge data point of Fig.17, MBT was evaluated through linear interpolation on the data sheet from Ford for zero EGR. Fig.18 gives the results as a function of dimensionless speed (we') and dimensionless throttle (0 ’). 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 DImeneIonIeee Speed Fig. 17: Cylinder Air Charge mee, 1995 Ford Escort 1.9 liter, using (26) The SAI multiplier at the measurement point of Fig.7 can now be evaluated using the SAI curve fit of Fig.9 and the MBTvalues of Fig.18. 23 30.000 , , 34.000 32.000 30.000 20,000 new [DBTDC] 20.000 24.000 _ _ 22.000 .2 0.3 04 I 0.5 I . 0.7 I 0.8 I 0.9 1 Dimenelonleee Speed Fig. 18: Calculated MBTusing Fig.17 and Mapping Data on the 1990 Ford Escort 1.9 liter obtained from Ford Motor Co. 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Dlmenelonleee Speed Fig. 19: Stoichiometric Fuel Conversion Efficiency, 1995 1.9 liter Ford Escort, using (19) and Curve Fits of Fig.9 and Fig.1O 24 The stoichiometric fuel conversion efficiency (Fig.19) as a function of dimensionless speed (we’) and dimensionless throttle (t9 ’) was calculated for the operating conditions of Fig.7, using (19) and the AFI and SAI curves of Fig.9 and Fig.10. The stoichiometric fuel conversion efficiency (Fig.19) is presented as a function of engine speed and throttle angle. Fuel conversion efficiency is however rather related to the mean manifold pressure (pm) than it is to throttle angle. Generation of the map (15) out of Fig.19 is done through a model for the air intake system. 25 Chapter 4 AIR INTAKE SYSTEM The results for the stoichiometric fuel conversion efficiency (Fig.19) were given as a function of throttle angle and engine speed. The data in Fig.19 give fuel conversion efficiency for an engine with idle air control active. Each data point in Fig.19 corresponds to a certain combination of throttle and idle air control. Representation of efficiency as a function of throttle angle only is less general. To avoid a multi-dimensional map of efficiency as a function of throttle angle, engine speed and idle air control, manifold pressure and engine speed are used instead as the independent variables to characterize the stoichiometric fuel conversion efficiency. dub/[AC Po—-> . Idle Alr Valve . To—> _:,\‘®E’ Intake ’ ”.2 Po V Manifold “" T0_, Throttle l 0 Fig.20: Air Intake System Signal Flow The air intake system will be studied to relate the mean manifold pressure pm to the control inputs of the induction system: the throttle angle (0) and the idle air control valve duty cycle (dufyIAc). This will allow conversion of the 26 stoichiometric fuel efficiency results of Fig.19 into a map with manifold pressure and engine speed as independent variables. A signal flow scheme for the air intake system (Fig.20) consists of the idle air valve, the throttle and the intake manifold. Moskwa and Hedrick (1989) give detailed model relations for the airflow into the manifold as a function of idle air valve duty cycle, throttle angle, environmental pressure (p0) and environmental temperature (T a). In general, one could write: moi: mat (dUtYIACa 0’ pm, p0! T0) (27) The mean mass airflow (rhea) out of the intake manifold equals the cylinder air charge (mee) times the number of cylinder fillings per second. For a four- stroke engine with n cylinders: ' =m - ' .. 28 more 0C 47: ( ) The cylinder air charge (mee) depends on different factors, such as manifold pressure and temperature, exhaust gas pressure, engine speed, etc. [Heywood, 1986, Servati, 1986]. For purpose of our analysis, we will assume dependency of the air charge on manifold pressure and engine speed only. mac = "'0ch we) (29) At steady operation, the mass airflow mm. into the intake manifold must equal the airflow ritm out of the intake manifold. With (27), (28) and (29): , n~w, "Imam-Yuma, pm’ P0,To)= mac (pm’we ) 471' (30) 27 The cylinder air charge (Fig.17) was estimated using the signal from the HEGO sensor and calibration data for the fuel injection system. With cylinder air charge known at every stoichiometric fuel conversion efficiency data point of Fig.19, (30) can be solved for the mean manifold pressure as a function of throttle angle, idle air duty cycle, environmental conditions and engine speed. V {iii Fig.21: Measured Mean Manifold Pressure, 1995 1.9 liter Ford Escort without Air Filter, po= 97.1 kPa, To = 24.5 °C Models for the idle air valve and the throttle valve were not generated. The mean manifold pressure (Fig.21) was obtained through direct measurement at the speed, throttle and idle air control conditions of the stoichiometric fuel 28 conversion efficiency data points (Fig19). The average output voltage of a manifold pressure sensor was recorded and related to the manifold pressure through sensor calibration. The map (29) for the air charge as a function of manifold pressure and engine speed can be found combining mean manifold pressure (Fig.19) and cylinder air charge (Fig.17) and elimination of the throttle angle through linear interpolation between data points (Fig.21). This completes the model relation (28) for the airflow out of the intake manifold. 0.00050 pmlkPa] Cylnder Alr 0mm m] Fig.22: Cylinder Air Charge as a Function of Manifold Pressure and Engine RPM, 1.9 liter 1995 Ford Escort, using Fig.17 and Fig.21 29 CONCLUSION A system's framework for the engine subsystems and their signal or power interactions was presented. Care was taken to obey causality when characterizing the interactions. Steady state mean value input-output relations for the different subsystems were derived based on dynamometer test data for the 1995 1.9 liter Ford Escort. Engine model control inputs are throttle angle, idle air control, fuel injector pulse width and spark advance. Engine output performance was formulated in terms of mechanical power or specific fuel consumption. Experimental procedures were proposed or references provided to obtain all model relations stated. A test stand for engine control research was developed and its ability to generate steady state engine control models demonstrated. The Cosworth Intelligent Controls |05460 Engine Control System ® was installed and used to vary fuel injection and spark timing. All sensors and actuators were calibrated and proved to function reliably. It was observed that steady laminar flow calibration results for the mass airflow sensor could not be used in the running engine due to lack of accuracy. If the mass airflow sensor is used to drive future engine control algorithms, care must be taken to software compensate for mass airflow sensor systematic errors as a function of engine speed and engine load. A more precise 3O dynamic flow model for the mass airflow sensor may yield better insight into its complex flow dynamics. The engine model presented was identified except for the following parts. The dependency of the Minimum Spark Advance for Best Timing on cylinder air charge and engine speed needs to be verified through direct measurement. Steady flow models for the throttle body and the idle air valve need to be generated. To measure the airflow contribution of the idle air valve, a series of tests without idle air valve could be run and air charge compared to those from tests with idle air valve. Airflow through the throttle and through the idle air valve are then related to the environmental conditions, the mean manifold pressure, the idle air valve duty cycle and the throttle angle. The map (15) for the stoichiometric fuel conversion efficiency as a function of manifold pressure and engine speed is found combining fuel conversion efficiency (Fig.19) and mean manifold pressure (Fig.21) and eliminating the throttle angle through linear interpolation between data points. This will complete the model for the Indicated Work block. The modeling strategy and measurement procedures proposed are applicable to any port fuel-injected spark ignited internal combustion engine without exhaust gas recirculation. The procedure delivers mean value steady state relationships only. Due to its causal formulation, the model can be extended dynamically by inclusion of state equations for the Intake Manifold 31 (state pm) and the Mechanical Dynamics (state we). Model relations (1, 2, 15, 22, 27, 28, 29) were all formulated in terms of the inputs and the state variables of the dynamic model. The relations stay valid, even under dynamic changes in inputs, mean manifold pressure or engine speed. 32 APPENDICES 33 APPENDIX A ENGINE-DYNAMOMETER SETUP A.1 Dynamometer Specifications A.1.) General Electric DC Electric Dynamometer Type: TLC-2464H, Form: FN Model: 260230 Voltage: 250 volt Current: 550 A Generator mode: absorbs up to 200 hp Motor mode: delivers up to 150 hp Speed: 2500-6000 RPM Load cell lever arm: 18.007" = 1.5006 ft Checking lever arm: 27.011" = 2.2509 ft A.1.2 Load Cell (south side) BLH Electronics, Inc, Waltham, Massachusetts Type: USG1C, Serial # 95910 Capacity: 1000 lbf Bi-directional load capability: (-) torque reading when loaded in compression (+) torque reading when loaded in extension 34 A. 1.3 Variable Reluctance Speed Sensor (shaft west end) Amphenol 165-34 8703 Type: ring gear, 60 teeth/revolution Terminal identification: A: +12 volt DC B: Direction output 0: Ground D: Frequency output E: Frequency output A.2 Dynamometer Sensor and Actuator Calibration A.2.1 Load CelWorque Display Calibration Weight applied at checking lever arm: 9.8 lbf Corresponding actual torque: 9.8 lb x 2.2509 ft = 22.1 ftlb South end lever arm torque reading: 252 ftlb compression North end lever arm torque reading: 17.8 ftlb extension Torque offset: (-25.2+17.8)/2 = -3.7 ftlb => Apply counterweight on North and lever Required counterweight: 3.7/2.2509 = 1.64 lbf South end lever arm torque reading with counterweight: -21.4 ftlb 35 North end lever arm torque reading with counterweight: 21.0 ftlb Comparison with actual torque (22.1 ftlb) => torque display accuracy i 1 ftlb A.2.2 Dynamometer RPM Display Calibration Calibration reference: BEI 360 pulses/revolution crankshaft encoder together with the Cosworth |05460 display. Calibration results are shown in Table A.1 and Fig. A.1. Table A.1: Dynamometer RPM Display Calibration Dynamometer Encoder Display RPM RPM 810 800 1009 1000 53!) lill 1:33 at 1616 1600 g” 1818 1800 52m 2022 2000 31800 2220 2200 gen 2425 2400 ‘“ em 2627 2500 an 1:110 18:0 2130 am am an) 2828 2800 WWII!“ 3030 3000 3236 3200 3434 3400 Fig. A. 1: Dynamometer RPM Calibration 3639 3600 3837 3800 4038 4000 A.2.3 Dynamometer Throttle Actuator The dynamometer throttle actuator is shown in Fig. A2. The throttle cable is attached to the actuator lever arm in such way that full actuation range corresponds to the throttle opening from 0° to 90°. Attach the cable to the 36 hole in the actuator lever arm that closely corresponds to full throttle opening range. Fig. A.2: Throttle Actuator Table A.2z Dynamometer Throttle Position Display Calibration Dynamometer TPS Throttle Display Angle Reading [deg] 4.8 0 145 5 176 10 e g 227 15 3 ,0 258 20 g 60 296 25 g 33 349 30 g e, 381 35 33 20 430 40 '- 13 :3; :3 0 200 400 600 800 two Freed 548 55 Wam°m "9 538 60 Fig. A.3: Dynamometer Throttle Position 534 65 Calibration 680 70 716 75 766 80 804 85 874 89.2 37 A.2.4 Dynamometer Throttle Position Display Calibration Calibration reference: Ford throttle position sensor (TPS) type F2CF- 9B989AA, L1 2H05 AH together with Cosworth IC 5460 display. Calibration results are shown in Table A2 and Fig. A.3. A.3 Englne—Dynamometer Coupling Design Design requirements: overall coupling length as small as possible - engine de-coupling from the dynamometer must be possible without moving the engine, such that engine aligmnent is maintained after de- coupling. - critical torque transmission: 100 hp at 3500 RPM - required speed range: 800-5000 RPM - coupling must withstand crankshaft torsional vibrations due to multi- cylinder discontinuous crankshaft torque production For design procedure, please refer to the Dodge ® Engineering Catalog [Reliance Electric Industrial Company, pp. 02-3 to 02-31, D1-5 to D1-9, 1993]. The design procedure is outlined on page 02-4. Torque transmission requirement factor: hp x 100/RPM = 2.85 38 Safety factor (refer to p 01-4): - driven unit: dynamometer :> 1.0 - driver unit: 4-cylinder gasoline engine => 0.5 safety factor = Z = 1.5 Actual torque transmission requirement = safety factor x 2.85 = 4.27 PX80 on page 02-4 satisfies torque requirements, but the maximum coupling speed is only 3500 RPM => go to high speed and flywheel couplings pp. 02-22 to 02-29. A flywheel coupling mounts directly to the engine flywheel with the coupling body inside the engine belthousing. This allows reduction of the overall coupling length. Coupling chosen: Paraflex Flywheel Coupling PH96, steel flange - Maximum speed: 5230 RPM > 5000 RPM => OK - Torque transmission capability factor: 4.5 > 4.27 => OK Use of a taper lock bushing at the side of the coupling connecting to the coupling shaft, allows to disconnect the coupling shaft and slide into the belthousing without moving the engine. Summary of the coupling parts: - PX80: taper lock flange part # 010604 - PF96: bolt ring assembly part # 011248 - PH96: flexible element part # 011228 39 - taper lock bushing, bush # 2012, 1 3/8" bore part # 117091 - shaft (engine side): diameter 1 3/8" over 2”, keyseat 5/16" x 5/32" - nominal shaft dimensions: length 12", diameter 1 1/2" The Paraflex flywheel coupling allows a limited degree of misalignment between the axes coupled (Fig. A4). The engine alignment must then be well within the tolerances given. Conclusion: the design reduces the coupling length outside the belthousing to 4". Fig. A.5 shows a picture of the coupling as mounted inside the engine belthousing. axis I in --. axis I *axis axis Maximum angular Maximum parallel misalignment misalignment Fig. A.4: Angular and Parallel Axis Misalignment Fig. A.5: Engine-Dynamometer Coupling 4O A.4 Engine Speclflcatlons 1995 Ford Escort 1.9 liter, inline four-cylinder A.4.1 Engine Block Cylinder bore Stroke Displaced volume/cylinder Compression ratio A.4.2 Engine Cooling System Coolant Thermostat Coolant pressure A.4.3 Fuel System Injector pressure drop Pressure downstream fuel pump (running) Injector type Injector flow rate Injector offset Compatible injector serial # (part # 2-18076) 3.23" = 8.204 cm 3.46" = 8.788 cm 0.4646 dm3 9.1 50-70 % ethylene glycol, 50-30°/e water 195 9F, Parts Master # 31399 12-15 psi 40 psi 35-40 psi (not running). 3045 psi saturation, 11-18 ohm 6.44 kg/hr 0.8 me 0280 150 907, 0280 150 937, 0280 150 938, 0280 150 941, 41 FOSE-9F593-A5A, FOSE-9F593-A1A (currently on engine), FOSE-9F593-B1A, FOSE-9F593-BSA, FOSZ-A, F13Z-A, CM-4673, CM-4722 A.4.4 Ignition System Firing order 1-3-4-2 Ignition principle spark-ignited Ignition configuration 2-coil electronic distributorless ignition Compatible spark plugs Champion 304 RSQYC, Autolite 5144 Spark wires 7 mm, double silicone core For detailed engine dimensions and specifications, please refer to Ahlstrand [Ahlstrand A., Haynes, J.H., 1996]. The engine control system is discussed in Appendix C. A.5 Engine Bracket Design The engine bracket must allow aligning the engine with the dynamometer shaft and attaching the engine to the dynamometer base plate. The existing front bracket and the attachment plate to the rear support pillar were modified for this purpose. Drawings of the new parts are found below (Fig A.6, Fig. A.7, Fig. A.9). 42 11.5.] Front Bracket Base Plate The front bracket base plate has two bolt slots for mounting the front bracket to the dynamometer base plate. Base plate dimensions are given in Fig. A.6. Plate 18" Thickness: V2" 1" 1" ~ 3.. 3.. 5 1" 12" 3 1" Fig. A.6: Front Bracket Base Plate A.5.2 Front Bracket U-Profile Bridge The front end of the engine is brought up to the height required for the dynamometer shaft and crankshaft to couple by means of a U-profile bridge. The bracket extensions of the belthousing mount onto the bridge. The bridge is welded onto the front bracket base plate. Bridge height is initially chosen 3/8" too high. Height finishing and welding onto the bracket base plate is done only at the time of engine alignment. Final bridge dimensions then carefully compensate for alignment errors. The U-profile construction is shown in Fig. A.7. 43 Profile Thickness: 11 1/4” 3/8" 1 1/2" U-profile All holes 5/8" a 1 3/8" 1 3/8" 2” 1 3/8" 3" 3" A 111/2" 13/3” Fig. A.7: Front Bracket Bridge and U-profile Fig. A.8 shows the engine supported by the front bracket. Fig. A.8: Engine-Front Bracket Mounting A.5.3 Rear Support Pillar Mounting Plate The rear support pillar mounting plate is mounted onto the rear part of the engine block and suspended onto the support pillar. 9.. 7 ‘/ ,, All holes 1/2" a 2 Plate Thickness: 1/2" 1 3/4" 1" 3/4" 1 1/4" ~ " 9’ 16 2 5/8" 4 Fig. A.9: Rear Support Pillar Mounting Plate After cutting and drilling, the plate is bend over an angle of 10 degrees (Fig. A. 1 0). Bending Line 10° Fig. A. 10: Rear Support Plate Bending Fig. A.11 shows the engine suspended onto the rear support pillar. 45 Fig. A. 11: Engine-Rear Support Pillar Mounting 46 A.6 Engine Alignment A bridge with pulley was built to facilitate engine alignment (Fig. A.12). Fig. A. 12: Bridge with Pulley Six engine block degrees of freedom need to be checked during the alignment procedure: vertical translation, left-right translation, front-rear translation, front-rear tilting, lateral tilting and rotation about the vertical axis. First, the unfinished front bracket is mounted onto the engine. Vertical translation is checked (engine crankshaft with respect to the position of the dynamometer shaft), as well as lateral tilting. Left and right pillars of the front bracket U-profile bridge (Fig. A.7) are finished following the errors measured. Finishing of the front bracket bridge fixes vertical translation of the coupling and lateral tilting. The front bracket base plate is now tightened to the dynamometer base plate and the finished front bridge is remounted to the engine. 47 Front-rear tilting is checked next: angular misalignment must be within the specifications of the coupling (Fig. A.4). The height of the rear support pillar is adjusted to compensate for angular misalignment. The only degrees of freedom unfixed at this point are the planar degrees of freedom in the horizontal plane. Left-right translation and rotation about the vertical axis must satisfy the coupling specifications (Fig. A.4). All three planar degrees of freedom are fixed at once by (1) marking the welding positions of the front bridge onto the front bracket base plate, as well as indicating the front bracket base plate position on the dynamometer base plate (2) shifting the rear end support pillar in the horizontal plane. The rear support pillar is tightened to the dynamometer base plate. The setup is taken apart again and the front bracket is now welded together. After alignment, coupling and dynamometer shafts are bolted together. Free rotation is checked by means of manually turning the coupling. Finally, the engine is motored at low speed for several minutes. If coupling shaft neither coupling feel warm, alignment is successful. A.7 Engine Cooling System The engine cooling system was modified. The engine coolant pump still drives the coolant circulation, but instead of using the engine radiator, the coolant is passed through a heat exchanger outside the building. A valve system is designed to allow easy draining of the coolant and to make it 48 possible to couple two different engines to the same heat exchanger. Fig. A.13 gives a picture of the valve system with the valves numbered for explanation. Fig. A. 13: Coolant Valve System Valves are open when the handle is parallel to the line. The arrows indicate direction of coolant circulation to the heat exchanger and the engines. Valves #1 and #2 shut off the lines to the heat exchanger. They are shut whenever draining or filling the engine block. In all other cases, these valves remain open to allow for circulation through the heat exchanger. A. 7.1 Heat Exchanger Switching between Two Engines Engine access valves #3 and #4 are open when engine #1 is operational. In such case, valves #5 and #6 need to remain closed to prevent flow through 49 engine #2. Engine access valves #5 and #6 are open when engine #2 is operational. In such case, valves #3 and #4 need to remain closed to prevent flow through engine #1. A. 7.2 Coolant Draining Procedure 1. Shut off the valves #1 and #2 to the outside heat exchanger. Open the access valves of the engine to be drained (either #3 and #4 or #5 and #6). Close the access valves of the other engine to prevent draining of the other engine. Place canister under the draining valves #7 and #8. Open the draining valves and wait for the cooling system to drain. Close the draining valves #7 and #8 after draining. A. 7.3 Coolant Refill Procedure 1. 2. Shut off the valves #1 and #2 to the outside heat exchanger. Make sure the draining valves #7 and #8 are shut. . Open the access valves of the engine to be refilled (both #3 and #4 or #5 and #6). Close the access valves of the other engine to prevent draining of the other engine. Add coolant to the coolant reservoir mounted above the engine block (Fig. A14) and wait for the air to vent. Close the coolant reservoir and open the valves #1 and #2. 50 6. Motor the engine at low speed. Check whether there is flow in the cooling system (even in motoring conditions, the coolant hoses from the reservoir to the oil filter should be warm due to compression heat). If there is no flow, open the coolant reservoir carefully while motoring the engine and release the compressed air in the lines. When a bubbling sound is heard which indicates starting flow, immediately close the coolant reservoir. 7. Stop the engine and shut the valves #1 and #2. 8. Add coolant to the reservoir if necessary. 9. Reopen the valves #1 and #2 and fire the engine to allow for the engine block to heat up and for the thermostat to open. 10. Repeat steps 7 and 8. A.7.4 Operating Conditions Coolant temperature: 180-195 9F Coolant pressure: 12-15 psi. Fig. A. 14: Coolant Reservoir 51 A.8 Exhaust System An exhaust fan (Fig. A.15) outside the building sucks the exhaust gases out of the exhaust pipe and blows them into the chimney. A.8.1 Fan Specifications Baldor Industrial Motor, Single Phase Cat: VL3513 Spec: 35013-199 Ser: F398 Power: 1 1/2 hp Voltage: 115/208-250 volt Current: 15/7.9-7.5 A Speed: 3450 RPM Frequency: 60 Hz Rating: 400 AMB-CONT Wiring: (low voltage) join wires 1-3-8, join wires 2-4-5. To reverse rotation, interchange connectors 5 and 8. A.8.2 Heat Shielding All exhaust components must be properly shielded and must ABSOLUTELY avoid contact with the coolant hoses, the coolant insulation or the spark wires. The exhaust manifold must be covered with a heat shield to protect the spark wires. 52 Fig. A. 15: Exhaust Fan 53 APPENDIX B DYNAMOMETER OPERATION This appendix uses information from an earlier engine-dynamometer startup description [Fitzpatrick, T., 1995]. The document was modified when necessary to account for changes made to the engine-dynamometer setup. B.1 Safety Checks 3.1.] Fire Safety 1. Coolant lines may not touch the fuel lines, or any of the wires of the electronic control unit. The fuel can ground clip must be grounded to engine ground and kept away from the battery. No liquid fuel may be apparent on the ground near the battery, on the engine or on the dynamometer base plate, such as often occurs after working on the fuel injection system or after refill of the fuel can. In such case, turn on the ventilation tubes and let the fuel evaporate first before running the engine. Spark wires may not touch the exhaust manifold. All exhaust components must be properly heat shielded and avoid contact with the coolant lines, flammable objects or parts that can melt. Fire extinguishers must be placed at both sides of the engine. 54 7. A manual emergency button near the dynamometer control box allows shut off of ignition and fuel supply to the engine. The emergency switching circuit is described in Appendix 0.4 Engine overheating is prevented by an over-temperature relay, which shuts off both ignition and fuel supply in case of overheating (Appendix 04). 8.1.2 Mechanical Safety 1. Every day of dynamometer testing, check whether the coupling bolts and taper lock nuts are tight. Make sure hose clamps on all coolant hoses are tight. Make sure there are no obstructions on the dynamometer or engine, such as rags, tools and cords. Make sure sensor cables don’t touch rotating parts and are kept away from spark wires. Check whether Hall effect sensor mounting bracket is tight. Make sure spark wires, fuel injectors and all sensors are properly connected. Make sure no data acquisition or measurement equipment is located within the plane of the rotating coupling. 82 Pro-run Check and Running Preparation 1. Check engine oil level. 55 . Check coolant level in the coolant reservoir above the engine (Fig. AM). When doing this, make sure to close the valves to the heat exchanger. . Make sure the battery is charged (12-14.8 V). . Plug in the exhaust fan. . Turn on the ventilation tubes above the engine (switch with red-yellow- green lights is located in green box attached to Tom’s office). . Connect the 12 V battery to the power cables from the engine control stand. Red is positive. . Connect fuel can to fuel system: A. Hose quick connectors are interchangeable B. Make sure fuel can ground clip is connected to the engine ground. . Make sure that the main valves for the cooling system are open, as well as the access valves to the engine being run (valve handles parallel to the pipe). . Turn on the fans for the heat exchanger. Switches are located on the wall directly above where the coolant pipes pass through. 8.3 Dynamometer Startup Fig. B1 and Fig. B.2 show the two main dynamometer electronic circuit parts: the DC drive, which contains the high voltage power electronics and the dynamometer control cabinet, which contains the control electronics. 56 Fig. B. 1: Dynamometer D0 Drive Fig. B.2: Dynamometer Control Panel 1. Turn on the main power to the dynamometer (the switch is located on the 480 V bus way). 2. Make sure that the EMERGENCY STOP buttons on the DC drive and on the control panel are pulled out. 57 . Turn on the DC drive (lift handle Into the upward position). The fan inside the DC drive cabinet should go on. . Turn on the display power by pushing the left red button in the middle of the control panel. The steps 5-7 require a key to operate the switch. . Turning direction of the dynamometer: engines turn counterclockwise when looking from the front end (the end of the crankshaft coupling to the dynamometer) to the rear end. Motoring the engine in the wrong direction severely damages the oil pump. Therefor: CAREFULLY CHECK ON THE TURNING DIRECTION BEFORE PROCEEDING WITH A TESTRUN. Turning the key in between the “forward” and “reverse” knobs on the control panel sets the turning direction. TO RUN AN ENGINE ON THE WEST END: PUT DYNAMOMETER IN “REVERSE” ROTATION (switch should light yellow), TO RUN AN ENGINE ON THE EAST END: PUT DYNAMOMETER IN “FORWARD” ROTATION (switch should light red). . Make sure the controller is set on “Manual”, not “Auto”. The switch should light yellow. . Make sure the controller is set on “Speed”, not “Current”. The dynamometer is not set up to run in the “Current” mode. The switch should light yellow. . With the “Fault Reset” button illuminated, push the “Drive Power On” switch. This will turn on the oil pump and the two fans at the West end of 58 the dynamometer. The “Drive Power On” switch should light green. The light of the turning direction switch will go on, as well as the lights of the “Manual” and “Speed” switches. If the “Fault Reset” button is initially not illuminated, the “Drive Power Oh” will not react. In such case: open the DC power drive cabinet with a screwdriver. DO NOT TOUCH ANY OF THE ELECTRONIC CIRCUITRYI Look for the display through the hole in the gray box at the bottom of the power electronics. The display should show “P00”, which is the reset location of the control program. If “P00” doesn’t show: push the blue button to the left of the display BY HAND (Fig. 83). Keep pushing the blue button until “P00” appears on the display. Close the DC drive cabinet. The “Fault Reset” button on the control panel should now illuminate. Push the “Drive Power On” switch and the system should react as stated above. If the system still doesn’t react: turn the D0 drive power off as well as the main power to the dynamometer. Check the fuses inside the D0 drive power cabinet. Replace bad fuses and repeat steps 1 through 8. 9. If the dynamometer has not been run for two weeks or more, stop at this step for 1/2 hour to allow lubrication. 10.Press the “Fault Reset” switch. The “Fault Reset” switch light should now be off. The “Fault Reset” button resets the speed scale to zero. IF THE FAULT RESET IS NOT PRESSED BEFORE PUSHING THE “RUN” BUTTON, THE SPEED SCALE HAS AN OFFSET AND THE DYNO MAY 59 START TO ROTATE IN THE OPPOSITE DIRECTION AS EXPECTED, EVEN WHEN ZERO SPEED IS INDICATED. 11.Make certain the “Throttle” and “Speed” turning knobs are turned all the way counter-clockwise. 12.Tum on the throttle controller by pushing the two yellow buttons on top of the control panel. Both yellow buttons should light. 13. Depress white “XFB” or “P/E” button on the throttle controller. These buttons define the dynamometer control mode (see below). WHILE RUNNING, THE CONTROL MODE MAY NEVER BE CHANGED! THE DYNO IS NOT SET UP TO RUN IN ANY OTHER CONTROL MODES THAN THE ONES MENTIONED: DO NOT PUSH ANY OTHER WHITE BUTTONS OR SEVERE DAMAGE MAY OCCUR. 14.Tum on fuel pump and engine ignition. The procedures for engine firing and shutdown are discussed in Appendix 0.7 for operation with the Ford Control System. 15. For a run in “P/E” mode: with the silver knob on “SP” (set point), turn the “Throttle” knob until it shows about 150 (or 15% throttle). In “XFB” mode: with the silver knob on “SP” (set point), turn the “Throttle” knob to set the desired load torque at idle (in ftlb, e.g. 60-70 ftlb for the Ford Engine). 16. Press the “Run” switch. The switch should light green. The main fan of the DC drive cabinet should go on. 60 Fig. 8.3: Dynamometer DC Drive Display Location 17.Tum the “Speed" knob until the engine is motored at 1200 RPM (high idle). IT IS NOT ADVISABLE TO RUN THE DYNAMOMETER AT LOWER SPEEDS. A scheme of the startup settings is given in Table 3.1. 61 Table B.l: Dynamometer Startup Sequence No. SETTING LABEL WEST DYNO EAST DYNO 1. EMERGENCY STOP PULLED OUT PULLED OUT 2. MAIN POWER ON ON 3. D0 DRIVE ON (handle up) ON (handle up) 4. DISPLAY ON (red button) ON (red button) 5. ROTATION REVERSE (yellow) FORWARD (red) 6. CONTROLLER MANUAL (yellow) MANUAL (yellow) SPEED (yellow) SPEED (yellow) 7. DRIVE POWER ON (green) ON (green) 8. FAULT RESET yellow light off yellow light off 9. THROTTLE KNOB totally left 10 SPEED KNOB totally left totally left 11. THROTTLE CONTROLLER ON (two yellow lights) 12. CONTROL MODE P/E PUSHED IN P/E PUSHED IN 13. SET POINT THROTTLE TO 150 14. RUN ON (green) ON (green) 15. SPEED 1200 RPM 800 RPM 62 3.4 Dynamometer Control System 3.4.] Control Display The “RPM” part of the display window (red LED. display on the left) always shows engine RPM. Calibration of the speed display is given in Appendix A2. The “performance knob” (the silver knob on the Throttle Controller) selects what system is monitored. The “performance monitor” (red LED. display on the right) displays the value of the selection of the “Performance Knob”: either torque or throttle. Calibration of the throttle display and torque display is given in appendix A.2. NOTE: pay careful attention to the units! These are NOT displayed, however they DO change depending on the position of the “Performance Knob”. 8.4.2 External Feedback Control Mode Throttle controller white push button in “XFB”. In this mode, you set the speed that the engine will run at, as well as the torque the engine is required to produce. Remark that this sets a requirement for engine power at the given speed. In this mode, the dynamometer is given control over the throttle actuation: the throttle will automatically open or close to try to achieve the required power setting at the RPM given. (i.e. the operator defines RPM and torque and throttle position is the variable). The “Performance Knob” has the following usable settings in this mode: 63 “XFB” = External Feedback. This is the actual reading from the load cell in foot-pounds. This is the torque that the engine is actually producing. “POSITION” = percent throttle x 0.1 “SP” = Torque Set Point in foot-pounds. This is where you set the load that the dynamometer will hold against the engine. To provide the engine from stalling: setting the load at a value greater than the engine can attain at the RPM given, will cause the throttle to fully open (WOT) in an attempt to reach the level given. Use the “Throttle” knob to adjust the set point. “FB” = Feedback from the load cell in foot-pounds. This should be the same as “XFB” 8.4.3 Position/Excitation Control Mode Throttle controller white push button in “P/E”. In this mode, you set the speed that the engine will run at, as well as the throttle position. In this mode, the dynamometer will automatically adjust the load the engine sees to achieve those settings (i.e. the operator defines RPM and throttle and load torque is the variable). Note: The dynamometer is only set up to use the “Position” function. Attempting to use “Excitation” will cause SEVERE DAMAGE to the 64 dynamometer and its components! Therefore, never push the red “Excitation” button on the throttle controller part of the control panel. The “Performance Knob” has the following usable settings in this mode: “XFB” = External Feedback. This is the actual reading from the load cell in foot-pounds. This is the torque that the engine is actually producing. “POSITION” = percent throttle x 0.1 “SP” = Throttle Set Point in percent throttle x 0.1. This is where you set the throttle position that the engine will run at. To dynamometer will automatically adjust the load against the engine to maintain these settings. Use the “Throttle” knob to adjust the set point. “FB” = Feedback from throttle actuator. This should be the same as “POSITION”. NOTE: IF THE DYNAMOMETER IS RUNNING lN “XFB” OR “P/E” AND SWITCHED TO THE OTHER SETTING, SEVERE LOADS MAY BE APPLIED OR REMOVED. For instance: in “XFB” the “SP” may be set to 80 (foot-pounds), but when switched to “P/E” the system reads the “SP” as 80 x 0.1 = 8 °/o throttle. This can cause quite a shock. 3.4.4 Loading the Engine in “XFB” Mode 1. Use the “Speed” knob to set desired RPM. The engine will always remain at that RPM, either motoring or absorbing. 65 2. To determine a throttle position required for a given load: set the “Performance Knob” to “SP”, then specify the desired torque load using the knob labeled “T hrottle”. The dynamometer will automatically load the engine to the torque level specified while opening the throttle to maintain the RPM set previously. Switch the “Performance Knob” to “Position”. This will display the throttle position required to produce the specified torque. To determine the torque for a given throttle position: cannot be done in the “XFB” mode. 8.4.5 Loading the Engine in “ P/E ” Mode (measurement of Torque-speed Curves) 1. 2. Use the “Speed” knob to set desired RPM. The engine will always remain at that RPM, either motoring or absorbing. To determine engine brake torque for a given throttle: set the “Performance Knob” to “SP”, then specify the desired throttle position using the knob labeled “Throttle”. The dynamometer will automatically load the engine to maintain the RPM under the specified throttle position. Switch the “Performance Knob” to “XFB”. This will display the torque produced at the throttle position specified. To determine the throttle position required for a given load: cannot be done in the “P/E” mode. 66 8.5 Dynamometer Shutdown 1. 7. 8. 9. Shut down the engine. Procedures for engine shutdown are given in Appendix 0.7 for operation with the Ford Control. . Turn down the “Speed” knob until the dynamometer has stopped. While approaching zero speed, be careful not to turn the dynamometer into reverse direction (this may occur due to shifting of the zero speed set point during the test run) Press the “Stop” switch below the “Run” switch. The main fan of the DC drive cabinet shuts off. Turn off the throttle controller by pushing the two yellow buttons on top of the control panel. . Press the “Drive Power Off” switch below the “Drive Power On” switch. . Turn off the display power by pushing the left red button. Turn off the DC drive by pulling down the handle. Turn off the main power to the dynamometer, located on the 480 V bus Turn off the fans for the heat exchanger. 10. It is advisable to let the exhaust fan as well as the ventilation tubes on for a couple minutes to allow exhaust gases and heat to be removed. Then unplug the exhaust fan and turn off the ventilation tubes. 1 1 . Disconnect the cables from the battery. 12. Disconnect the fuel can and store it in the “flammables” cabinet. 67 Table 8.2: Dynamometer Shutdown Sequence No. SETTING LABEL WEST DYNO EAST DYNO 1. SPEED 1200 RPM 800 RPM 2. SET POINT THROTTLE TO 150 3. IGNITION OFF OFF 4. SPEED KNOB totally left totally left 5. THROTTLE KNOB totally left 6. STOP push red switch push red switch 7. THROTTLE CONTROLLER OFF (two yellow lights off) 8. DRIVE POWER OFF (red) OFF (red) 9. DISPLAY OFF (red button) OFF (red button) 10. DC DRIVE OFF (handle down) OFF (handle down) 11. MAIN POWER OFF OFF 68 APPENDIX C ENGINE OPERATION USING THE ELECTRONIC ENGINE CONTROL MODULE FROM FORD C.1 Functional Overview The electronic engine control module sets ignition and fuel injection timing over the entire speed-load operating range of the engine, as well as the duty cycle of the idle air control (IAC) valve. Control algorithms for ignition and fuel injection are based on static mapping information with additional trimming routines for exhaust gas oxygen (EGO) feedback and cold start enrichment. Camshaft and crankshaft position sensors provide triggering information for ignition and fuel injection timing. Throttle position sensor (T PS) and mass airflow (MAF) sensor provide information on engine load. The exhaust pipe contains a heated exhaust gas oxygen (HEGO) sensor for use in the EGO feedback fuel injection trimming. The cooling hose leaving the oil pump contains the engine coolant temperature (ECT) sensor used during startup. The intake system contains an air charge temperature (ACT) sensor used for fuel injection trimming. It is remarked that the ECT and ACT configurations were changed with respect to the original engine setup. Although the production engine is equipped with an exhaust gas recirculation (EGR) valve, the engine on the dynamometer test bed doesn’t have EGR installed. 69 Additional analog displays and gauges provide oil pressure, coolant temperature, battery voltage, ignition current, coolant pressure and fuel pressure for quick checking during operation. The engine is equipped with a multi-point sequential port fuel injection system and a dual coil electronic distributorless ignition system (EDIS). The engine control system consists of the control module, a breakout box for monitoring control signals, an operator panel with manual switches and the emergency switch below the dynamometer control panel. Limited information was available on the Ford production control system. Although not complete, the following sections contain the information provided by Ford as well as additional data extracted from the engine control system through dynamometer tests. Also included are wiring diagrams, interface characterization (if available) and calibration data for sensors and actuators. C.2 Sensors The sensors provide input signals to the electronic control module and the electronic distributorless ignition system. C.2.1 Crankshaft Position Sensor (Fig. C.1) Part #: Motorcraft # FOEE-80315-A28 Principle: Variable Reluctance Sensor Features: 36 teeth, one tooth missing 70 Measured variables: engine RPM, crank angle, crank angle reference Function: - provide degree-based trigger signal for ignition and fuel injection - provide RPM as mapping input to the EEC Fig. C. 1: Crankshaft Position Sensor C.2.2 Camshaft Position Sensor (Fig. C.2) Part #: Motorcraft # FOEE-68288-A1A Principle: undetermined Measured variable: camshaft reference position Function: provide reference pulse for the sequential fuel injection system. Remark that the dual coil ignition system doesn’t need a cam reference since spark fires during both exhaust and compression strokes. 71 Fig. 0.2: Camshaft Position Sensor (Located behind the Intake Manifold) C.2.3 Throttle Position Sensor (Fig. C3) Part #: Motorcraft # F2CF-93989-AA Principle: rotary potentiometer Measured variable: throttle position Function: provide throttle position as mapping input to the EEC Terminal identification: A: Ground B: Signal, low at closed throttle — high at wide-open throttle C: +5 volt DC 72 Fig. 0.3: Throttle Position Sensor The overall resistance (terminal A to terminal C) equals 3.48 kg. The resistance between terminals A and B varies linearly as a function of throttle angle (Fig. 0.4) from 3.33 k!) at closed throttle (0 = 0°) to 0.73 k!) at WOT (9 = 88.9 °). For Fig. 0.4, it was assumed that in between closed throttle and WOT the throttle resistance varies linearly. ' ' 3.36-0.73 R =3.33—-——- . :TPS. . 889 . 4 . I A I A 10 20 so 40 50 Tllotlla And. [dog] Fig. 0.4: TPS Resistance 73 Fig. 0.5: Mass Airflow Sensor C.2.4 Mass Airflow Sensor (Fig. C.5) Part #:’94-’95 engine models: Motorcraft # F37Z-128579-A or F37Z-123579-F ’91-'93 engine models: Motorcraft # FOCZ-12B579-A IT IS UNCERTAIN WHETHER THE SENSOR ON THE ENGINE IS COMPATIBLE WITH THE ENGINE CONTROL SYSTEM. The sensor installed on the engine has the following part # which is different from the ones mentioned: FOCF-12B579-A. Calibration data given is for the FOCF- 123579-A model only. Principle: hot wire anemometer in Wheatstone bridge Measured variable: total mass airflow in the intake (= throttle flow + IAC valve flow) Function: provide mass airflow as mapping input to the fuel section of the EEC 74 Terminal identification: A: +12 volt DC (Vuf), battery supply B: Ground C: Signal (-) D: Signal (+) Table C.1: Mass Airflow Calibration (Sensor FOCF-12B579-A) If! "(9’th V/me 55.56 0.147 63.70 0.173 69.63 0.179 75.80 0.187 79.38 0.194 83.84 0.199 87.41 0.202 97.51 0.212 § 103.86 0.220 s 119.14 0.229 128.03 0.234 . _ _ 136.92 0.234 V ’; : 3 142.00 0.235 ,0, _ ............... . . -— F £0...0.1.42 m .-..-. 37.91. .+. 00978 .. . . 145.81 0.236 ref 3 3 ‘ 154.03 0.244 00 5b "in GO 230 2;” 161 .49 0.253 mm M! 172.10 0.258 183.39 0.267 Fig. 0. 6: Mass Airflow Calibration 196.29 0.275 (Sensor FOCF-12BS79-A) 205.97 0.288 224.05 0.295 245.51 0.303 259.17 0.311 266.98 0.317 75 The voltage-airflow input-output relations of the mass airflow sensor were determined by running the sensor in the intake in series with the Hitachi/Ford sensor #ES-E82F-12B579-AA as a reference. The Hitachi/Ford sensor has known voltage-airflow characteristics. During calibration, the reference sensor was powered off a steady 12-volt voltage supply, whereas the calibrated sensor was powered off the car battery. Changes in the battery voltage me during the test run were recorded and compensated for by calculating sensor output voltage as a ratio to the battery voltage me. NOTE THAT CALIBRATION RESULTS ARE ONLY VALID IF THE VOLTAGE- AIRFLOW CHARACTE-RISTICS FOR THE HITACHI/FORD SENSOR WERE ACCURATE. Calibration results are shown in Fig. C6 and Table C.1. C.2.5 HEGO Sensor (Fig. C. 7) Part #2 not available Principle: oxygen driven voltage difference across ZrOz material Features: sensor contains heating resistance, powered off the car battery Measured variable: exhaust gas oxygen content Function: provide relative A/F ratio information to the fuel section of the EEC Terminal identification (refer to Fig. C.8): A: +12 volt DC, battery supply (white wire) B: ground (white wire) C: signal (black wire) 76 The sensor signal is activated only after the sensor reaches operating temperature (above 300 °C). The sensor switches between high and low voltages depending on the relative A/F ratio 9» of the exhaust gases. The switching voltage levels depend on the operating temperature. For the engine block operating above 195 °F, rich mixture (k1) corresponds to a sensor voltage > 800 mV and lean mixture (791) corresponds to a sensor voltage < 70 mV. Fig. C. 7: HEGO Sensor A 12 v RHEGO = 6.6a . j: A0 BO HEGO cO Sensor C .1! Signal Connector Pin Fig. 0.8: HEGO Terminal Identification 77 C.2.6 Air Charge Temperature (ACT) Sensor Part #: Motorcraft # FOSF-9F472-AA Principle: temperature dependent resistance, thermistor Measured variable: intake air temperature Function: provide intake air temperature information to the fuel section of the EEC Terminal identification: 5 volt DC power and ground The intake system has been modified with respect to the production engine. The ACT sensor is threaded into a transparent flow straightener in the intake (Fig. 0.9). Change of sensor resistance with temperature is given in Fig. C10 and Table C.2. Fig. 0.9: Air Charge Temperature Sensor 78 Table C.2: ACT Sensor Calibration __ e76.26—I2.78>(TACT+273.I5) _ . 20 Tommi. [dog cl Fig. C. 10: ACT Sensor Calibration (Sensor F2ZF-12A697-AA) Fig. C. 11: Engine Coolant Temperature Sensor C.2.7 Engine Coolant Temperature (ECT) Sensor (Fig. C.11) Part #: Motorcraft # E4AF-12A848-AA Principle: temperature dependent resistance, thermistor 79 Measured variable: block coolant temperature Function: - provide coolant temperature information to the fuel section of the EEC - provide switch off signal to over temperature emergency relay Terminal identification: 5 volt DC power and ground The engine coolant system has been modified with respect to the production engine. The ECT sensor is threaded into the rubber hose connecting the oil pump to the thermostat housing (Fig. 0.11). Change of sensor resistance with temperature is given in Fig. 0.11 and Table 0.3. Calibration was done with the OMEGA ® Engineering HH 81 digital thermometer (chromeI-alumel thermocouple) as a reference. Table C.3: ECT Sensor Calibration (Sensor E4AF-12A848-AA) T n .. . . . 22.6 31.4 i i I > 24.9 27.2 .. 25.6 25.8 E” 27 24.2 gzo—' 30 20.5 .1; 35 15.2 40 10.9 45.1 8.3 .. 50 6.3 . . . 1 1 . 55 51 2° 3° ‘° Tmazgoioog c1 00 70 80 61.7 2.9 Fig. C. 11: ECT Sensor Calibration (Sensor E4AF-12A848-AA) 80 C.3 Actuators C.3.1 Fuel Injectors Part #: Motorcraft #FOSE-9F593-A1A (gray body, labeled “A1 ” to “A4”) Part numbers of other compatible injectors are given in Appendix A.4. It is noted that the injectors on the spare engine (black body, labeled “B1” to “B4”) were found compatible as well. Principle: solenoid valve Resistance: 14.8-15.0 (2 (saturation injector) Mean Flow Rate: 6.44 kg/hr, Mean offset : 0.8 ms Terminal identification: 12 volt DC battery supply and ground In order to run routines for controlling A/F ratio, it is of crucial importance to know the exact flow rate of the injectors as well as their opening time (or offset). Flow rate determination was done in a flow bench test using the Cosworth |05460 control system. In a flow bench test, the injectors are fired a given number of times with a known pulse width. The total mass of fuel injected is weighted and divided by the number of injections to yield fuel mass per injection. The flow bench test is repeated for different values of the injector pulse width. A graph of mass per injection [gram] versus pulse width [ms] is generated and a linear least square fit obtained. The slope of the linear approximation is equal to the injector flow rate [kg/s]. The intersection of the curve with the pulse width axis is equal to the injector offset [ms]. 81 Flow bench test results for the injectors (FOSE-9F593-A1A) on the engine are given in Fig. C12. The injectors on the engine are labeled “A1” to “A4” with red ink corresponding to the plots of Fig. 0.12. Flow bench results for the black body injectors on the spare engine (labeled “B1” to “B4”) are not shown, but mean injector flow rate and mean injector offset were found to be the same as for the gray body injectors currently on the engine. C.3.2 Idle Air Control (IAC) Valve (Fig. C.13) Part #: Motorcraft # FZCE-9F715-AB Principle: solenoid valve Resistance: 10.0 9 Terminal identification: 6-12 volt variable duty cycle supply from the EEC 0.03 0.03 : ~ _ 0.025 ....... Flow. Rate .1- 6.5. kg/hrg' ............. __ 0025 ....... Flow 86:64.64 new ............. £0.02 ....... Offset-09m ... £0.02. Offsetsoems ’g I j .5 . E 0.01 5 E 0.01 5 8 ’8 3 001 T ....................................... B 0.01 » u”. 51 0.005.......... ............................. 0005. ............................... 0 ‘ - 0 . 0 5 10 15 0 5 1 0 15 Injector PW [ms] Injector PW [ms] Injector A3 calibration curve Injector A4 calibration curve 0.03 2 v 0.03 7 7 —— 0.025 ....... Fl” B§‘°.' .614. km.“ ............ _ 0.025 ....... 5'9“! .3819'364. kg/hr. ............ '5 . . a 0.02 0.02 .g . E 0.01 5 g 0.01 5 ‘5 E 0.01 g 0.01 » E .2 0.005 0.005 4' . o . 00 5 10 15 O 5 10 15 Fig. C. 12: Flow Bench Test Results for Gray Body FOSE—9F593-A1A Fuel Injector A1 calibration curve Injector PW [ms] Injectors Injector A2 calibration curve Injector PW [ms] Fig. C. 13: Idle Air Control Valve C.4 Operator Panel Wiring Diagram and Emergency Switching The operator panel forms the operator interface to the engine electronic system. It contains a bench of manually operated switches, relays for emergency operation and analog display windows. It also supplies battery power to the different engine subsystems and provides a common ground for all devices connected. Fig. 0.14 shows a picture of the front of the operator panel. Modifications to the panel were made: all dysfunctional wires and circuits were detached and the switching electronics changed with respect to the original setup in order to insure safety in case of emergency. C4. 1 Switching electronics and relays Manual switches on the panel are open when they are in the down position. There are six manual switches and one push button. From the left to the right: starter motor push button, ignition switch, fuel pump switch, unused switch, CAT PROTECT switch, PED switch and SPOUT CUTOFF switch. The upper row of 83 the front panel further contains three lights: ignition light (yellow), over temperature warning light (blue) and an unused red light. There are four numbered relays on the panel, two on the front and two on the back: over temperature relay (relay #1), ignition relay (relay #2), option relay (#3) and start relay (#4). In addition, there is one relay hanging at the backside. The emergency push button (red on yellow box) is located on the bottom portion of the dynamometer control panel. Fig. C. 14: Front of the Operator Panel The switching scheme for powering the engine electrical subsystems is given in Fig. 0.15. The ignition switch activates main power to the fuel injectors, the 84 ignition module, the idle air control valve, the EEC and all sensor circuits. Remark that these functions are not separated: one cannot run ignition without applying power to the fuel injectors and the idle air valve. The fuel pump switch turns on battery voltage to the fuel pump. The fuel pump circuit is separated from the ignition circuit. This gives the operator the ability to motor the engine without supplying fuel to the fuel rail (engine not firing), while all other engine control electronics (fuel injectors, spark, idle air control valve and sensor l/O lines) are active as during normal operation. Ignition Over Temperature SWitCh Emergency Push Button Relay , EEC, IAC valve, \ j ‘ Spark, Fuel Injectors 4_ —o/———- Fuel Pump ‘: Battery J Fuel Pump Switch L Commoh Engine- Battery Ground Fig. C. 15: Switching Scheme for Power Supply to the Engine Electrical Subsystems The over temperature relay and the emergency switch. are placed in series with the fuel pump and ignition switch. Both will switch off ignition and fuel supply to the engine, as is required in an emergency shutdown. The emergency push button is closed (power supply) if pulled out, it is open (power shutdown) if pushedin. 85 The battery power supplied to the engine electronic systems and the fuel pump does not flow through the manually operated ignition and fuel pump switches. The ignition switch provides a signal to the ignition relay. It is the ignition relay that actually applies power to the engine electronic systems. The fuel pump switch provides a signal to the option relay. It is the option relay that actually applies power to the fuel pump. Battery power does however flow through the emergency push button and through the over temperature relay. The implementation of the switching action of Fig. 0.15 through manual switches, push buttons and relays is shown in Fig. 0.16. The four main relays all have 5 terminals (labeled 1 to 5), with some terminals having two connecting pins. The main power supply to the relay comes through connector #5. Between connector #4 and connector #5 the relay has an internal coil. Outside the relay and also between connector #4 and connector #5 there’s a resistor in parallel with the coil. The relay is then a switch, which connects terminals #1 and #3 if current flows through the coil. Terminal # 1 has battery power (12 volt) connected. Terminal #3 is connected to the circuit being powered by the relay. Relay operation is then straightforward: if terminal line #4 is high, no current flows through the coil and the relay is not activated. Terminals #1 and # 3 don’t connect, such that the circuit connected to terminal #3 is not powered. If terminal line #4 goes low, current flows through the coil and the relay is activated. Terminals #1 and #3 connect such that the circuit connected to terminal #3 is powered. 86 " Battery Over Emergency I Temperature Push Button _ Start Relay (SPDT) Relay (SPDT) 5 5 r --------- T E 4 Over Temperature J l 1 Signal : i ‘ —|j2 v 12 v]— 1 5 L"-> (— Starter ‘J I L2 NC Push Button NC N # 1 3 NO 0 3 # 4 Over Temperature Warning Light Starter Motor Ignition . Option Relay (SPST) Relay (SPST) .-‘..1 i j ----- ,_ ,. I i i 1 —j:2 v I 1 L, l . . 12 V [— J 2 Ignition Fuej " — SWitCh Switch __ 2 # 2 3 3 # 3 EEC, IAC valve, spark, fuel injectors Fuel pump j_ i Fig. C. 16: Operator Panel Switching Operation Terminal #2 allows placing relays in series with one another. The over temperature relay (#1) and the start relay (#4) differ from the ignition relay (#2) and the option relay (#4), as far as terminal #2 is concerned. For relays #1 and #4, terminal #5 intemally connects to terminal #2 if the relay is NOT active 87 (terminal #4 high). If the relay is active (terminal #4 low), terminal #5 and terminal #2 disconnect. For relays #2 and #3, there is no internal connection between terminal #2 and terminal #5 whatsoever, irrespective of whether the relay is activated or not. For relays #2 and #3, terminal #2 is then dysfunctional. Switching operation can be read from Fig. 0.16. If the emergency push button is pulled out, battery power is supplied to terminal #5 of the over temperature relay. As long as the temperature signal stays high (no over temperature), the over temperature relays passes through power to terminal #2 and by this to terminal #5 of both option relay and ignition relay. Turning the ignition switch on activates the engine control electronics because it brings terminal #4 of the ignition relay to ground. It will also turn on the yellow ignition light. Turning the fuel switch on activates the fuel pump, because it brings terminal #4 of the option relay to ground. If over temperature occurs, the over temperature relay is activated, by this shutting off the power to both the ignition and the option relay. The fuel pump and the engine control electronics are shut down. In addition, the over temperature relay powers the blue warning light. If the emergency button is pushed, no power is supplied any more to the option and the ignition relay, such that the fuel pump and the engine control electronics shut down. The start relay is stand-alone with respect to the other electronics of the operator panel. Pushing the start button, which supplies power to the starter engine, activates the start relay. Remark that when operating the engine with the 88 dynamometer, the dynamometer itself is used for startup. The starter engine electronics were however left intact, such that a starter engine can still be hooked up to the operator panel. Remark: the function of the hanging relay at the back of the operator panel is undetermined. This relay was most probably the original fuel pump relay (a function now taken by a different relay). Wiring of the hanging relay was left intact. It never activates the way it is currently wired. It is therefor dysfunctional, but it might have its use when wiring connections are changed appropriately. C.4.2 Other Operator Panel Manual Switches The SPOUT CUTOFF switch, when turned on, generates an interrupt to the engine controller. In response to the interrupt, the controller reduces spark advance with respect to the original engine control settings. The effect of the SPOUT CUTOFF switch on spark advance was not investigated in detail. The function of the CAT PROTECT switch is undetermined. Turning it on applies battery power to the little black square box on the front panel (upper right comer). The function of the little black square box is undetermined. The function of the PED switch (originally labeled “fuel pump”) is uncertain. It interconnects with a troublesome electrical circuit, involving the hanging relay, the ignition switch, the little black square box on the front panel and a line connecting the operator panel to the EEC (probably an interrupt line). In order to power the line to the EEC, the hanging relay must activate, which never happens in the current setup. 89 When studying the operator panel, all switches with unknown functionality and circuits connected to these switches were left intact, IF these circuits somehow interconnect to the EEC or sensors. In all other cases, switches were disconnected and wires removed. C.4.3 Analog Display Devices The operator panel contains two analog display windows. A voltmeter (battery voltage) and an ampere meter (current drawn by the starter engine or the engine electronics). The current indicated on the ampere meter does not include the current drawn by the fuel pump or the distributorless ignition system. An additional analog display with three windows is mounted against the steel pillar, which supports the pulley rail above the engine. The gauges monitor oil pressure (lower window) and coolant temperature (upper window). The middle window, which shows current, is not connected. The display lights are powered through the operator panel and light if the ignition switch is turned on. Two pressure checking gauges were installed, one on top of the coolant reservoir and one in the line that connects the fuel pump to the fuel injector rail. C.4.4 Wiring to the ECC, the EDIS and the Sensors The wire connections between the operator panel, the ECC, the EDIS and the sensors were not studied in detail. Wiring diagrams for these connections are not yet available. Sensor interface characterization can be found in section C.2. Sensor input signals to the ECC as well as ECC output signals to the fuel 90 injectors and the IAC valve can be monitored off the ECC breakout box as explained in section 0.5. C.5 Breakout Box and Control Signal Monitoring C. 5. I Breakout Box Pinout Chart The breakout box of the Ford control system has 60 plug-in connectors for monitoring the controller’s l/O signals on the oscilloscope (Fig. C.17). A chart with pin #, circuit # & wire color and signal definitions is given in Table 0.4. The engine is not equipped with EGR, Canister Purge Solenoid, Air Conditioning, Clutch and Cooling Fan. Signal lines of the breakout box associated with these functions are marked “(n/a)” (not active). Signal lines which function are yet unidentified are marked with a question mark. The chart was copied from an original fax from Ford titled “Connector Faces/Pinout Charts 150-10” and extended with additional information on the EEC I/O lines out of Ahlstrand (1996). Fig. 0.17: Ford Controller Breakout Box 91 Table CA: EEC Breakout Box Pinout Chart Pin at Circuit Circuit Function Pin 11 Circuit Circuit function 1 330 (DB/R) Keep Alive Power 31 386 (R/BK) Cooling Fan Hi speed output We!) 2 - NOT USED 32 - NOT USED 3 150 (W/BK) Vehicle Speed Sensor (VSS) DIF (+) 33 108 (W/DB) EGR Vacuum Regulator (EVR) (n/a) (n/a) 4 153 ® Identification Diagnostic Monitor (IDM) 34 63 (LG/BK) Signal return (NOT USED) 5 - NOT USED 35 719 (YNV) Cooling Fan Lo speed output (n/a) 6 57 (DB) Vehicle Speed Sensor (VSS) DIF (-) 36 156 (LGNV) Spark Angle Word (SAW) (n/a) 7 62 (DBNV) Engine Coolant Temperature (ECT) 37 101 (W/R) V PWR (7) 8 121 (Y/DG) Data H (7) 38 - NOT USED 9 87 (DG/Y) Mass Air flow return 39 - NOT USED 10 707 (DG/BK) A/COn Input (n/a) 40 599 (BK/DG) Ground 11 - NOT USED 41 128 (O) CID (7) 12 105 (Y/O) Injector #3 Output 42 127 (08/06) CID (7) 13 115 (DG/O) Injector #4 Output 43 171 (DGNV) Octane Adjust (7) 14 - NOT USED 44 - NOT USED 15 94 (OM) Canister Purge Solenoid Output (n/a) 45 - NOT USED 16 78 (R/DB) Ignition Ground 46 63 (LG/BK) Signal return 17 129 (Y/BK) STO/MIL = EEC Control line 47 71 (RM) Throttle Position 18 - NOT USED 48 118 (LG/Y) STI = EEC Control Line 19 102 (BK/PK) Fuel Pump Relay Output (FPM) (n/a) 49 85 (O/BK) HEGO ground 20 - NOT USED 50 143 (BR/BK) Mass Air Flow 21 83 (DB/O) Idle Speed Control Valve (ISO) 51 - NOT USED 22 103 (LG) Fuel Pump Relay Input (PF) 52 - NOT USED 23 - NOT USED 53 154 (LG/R) Shit Indicator light We) 24 - NOT USED 54 702 (DB/BK) WOT (A/C cutout (W/C)) (n/a) 25 109 (W/DG) Air Charge Temperature (ACT) 55 - NOT USED 26 85 (LG/W) VREF 56 69 (DGNV) Profile Ignition Pickup (PIP) 27 145 (DB/Y) PFE 57 101 (W/R) V PWR (7) 28 122 (Y/DB) Data (+) (7) 58 106 (Y) Injector #1 Output 29 116 (DG/DB) HEGO Input 59 116 (DG/R) Injector #2 Output 30 62 (BR/Y) Park/Neutral Input or Clutch Interrupt 60 999 (BK/D6) Ground Sw. Input (n/a) C.5.2 Control Signal Monitoring The most important |/O signals are given below. Remark that some sensor signals have a separate ground shielded from the ignition ground. Injector #1 output: between pin 58 & ground Injector #2 output: between pin 59 & ground Injector #3 output: between pin 12 & ground 92 Injector #4 output: between pin 13 & ground Spark: between pin 16 & ground OR from inductive pickup probe around spark wire Mass airflow: between pin 50 81 pin 9 HEGO Sensor: between pin 29 and pin 49 IAC valve input: between pin 21 and ground C.5.3 Measuring Spark Advance To monitor spark signals on the oscilloscope, use the signal from the Hall effect sensor on the camshaft (occurs once every engine cycle) as a trigger. The cam signal is obtained from the Cosworth front panel BNC connector labeled “sync”. Make sure the triggering is stable before proceeding. Every trigger event, spark plugs fire twice (dual coil system): cylinders #1 and #4 fire together and cylinders #3 and #2 fire together. The firing sequence is 134-2. The Hall effect trigger signal was calibrated to occur at 41.6 degrees BTDC compression of the first cylinder in the firing sequence (cylinder #1). The time interval AtSA between the occurrence of the trigger and the occurrence of the spark is related to spark advance SA [deg BTDC] through RPM and the number n,- of the plug iin firing sequence: SA = —41.6° + RPM 60 .Ats, .360°-(n, — 1)- 180° (C.1) 93 TO OBTAIN A CLEAR SPARK SIGNAL USING AN INDUCTIVE PROBE AROUND THE SPARK WIRE, MAKE SURE THAT: 1. the probe doesn’t touch other spark wires 2. the probe doesn’t touch the engine block 3. the probe is put around the wire near the coil (NOT near the spark plug) For #1 and #2: the probe may pick up interference from other spark plugs. For #3: it has been observed that when the probe touches the spark wire near the spark plug, the trigger (cam signal) may disappear and the oscilloscope display for the spark becomes unsteady. This is due to formation of small static charges on the outside of the spark wires near the spark plug. These charges raise the voltage potential of the probe ground above engine (AND oscilloscope) ground, from which results a ground loop through the oscilloscope to the Hall effect sensor. C.5.4 Measuring Injection Timing Use the signal from the Hall effect sensor on the camshaft (occurs once every engine cycle) as a trigger. The injector phase angle (= the crank angle at which injection starts) can be measured the same way as spark advance (equation C.1). The fuel injector pulse width is the time the injector signal stays low. 0.6 Control System Operation and Mapping The EEC outputs signals to the EDIS for firing the spark, actuates the IAC valve and fires the fuel injectors based on the input signals it receives from the sensors. No detailed information was available on the code currently loaded into 94 the EEC micro-controller. Through elaborate testing of the engine in different regimes, engine maps were extracted. The maps currently downloaded into the EEC were found not to be compatible with engine mapping information received from Ford (Appendix D). This section gives as much information on the current EEC settings as could be obtained through dynamometer tests. C. 6. 1 Base Spark and Fuel Maps in terms of Throttle Angle To generate base spark and base fuel injection timing maps, it was assumed that the EEC uses the signal from the throttle position sensor as a measure of engine load. This instead of using the signal from the MAF sensor, which tends to be reliable only in a specific load-speed region. Base spark timing consists of a map of spark advance SA as a function of engine RPM and throttle angle 9 (Table C.5, Fig. C.18). Base injection timing consists of a map of injector flow rate thf as a function of engine RPM and throttle angle 9 (Table 0.6, Fig. 0.19). The base fuel injection map uses flow rate tit, instead of injector pulse width PW as the mapped variable. This has the advantage that the map becomes independent of the type of injectors used. For convenience, a fuel map for the PW of the injectors on the engine (FOSE-9F593-A1A, offset = 0.8 ms, injector flow rate info: 6.44 kg/hr) is given in Table 0.7. The pulse width given is the OVERALL pulse width, i.e. including injector offset. For conversion of PW into fuel flow rate in, , use: mf = ".110 . PW -ofiset _ RPM -n (0.2) 1000 120 95 with n = number of cylinders, PW and offset in [ms] An inductive probe for the spark on cylinder #1 generated the spark signal. The signal from injector #1 was obtained from the breakout box. How to calculate spark advance and injector pulse from an oscilloscope measurement is discussed in section 0.5. The HEGO feedback control (see later in this section) slightly alters the fuel injector PW over time. Pulse width measurements were made with the HEGO feedback mode activated. To somehow compensate for these changes in fuel injector pulse width, two measurements were made and the average calculated. Base fuel flow rates and base pulse widths shown in Table 0.6 and Table C.7 correspond to the average values. C. 6.2 Discussion of the Base Timing The base spark timing map is surprisingly not very dependent on the speed-load operating conditions. Spark advance varies from 10 to 14 degrees only, whereas one would expect values of up to 20 or even 30 degrees advance at high RPM. Spark advance is set very conservative, at a value much lower than MBT (minimum advance for best torque). The engine can clearly output more power than is obtained with the spark settings downloaded in the EEC. The fuel table shows that at high RPM and load, the injectors are near their full capacity of 4*6.44 = 25.8 kg/hr. The injectors almost continuously spray fuel at those conditions. 96 Table C.5: Spark Advance = f (RPM, 0) SA [DBTDC] '70 EnglneaRPM g g 3 § § 3 E Fig. C. 18: Base Spark Advance Map 97 Table C.6: Fuel Flow Rate = f (RPM, 0) ' 9 [°] mt ../" ./' 20.00 15.00 Fuel Flow Rate 5 ~ ; [kg/hr] ’ 10.00 1 5.00 ~ 0.00 . 70 40 Throttle Angle [de N N § § Engine RPM ‘7 E Fig. C. 19: Base Fuel Flow Rate Map 98 Table C.7: Injector PW = f (RPM, 0) [FOSE-9F593-A1A only] n‘z, 9I°I 83hr] RPM 10 20 30 40 50 60 70 80 120014.80 15.70 1400 14.30 16.15 16.70 16.50 1600 13.20 15.50 15.80 16.75 17.10 17.40 17.90 22.40 180012.50 15.25 16.15 16.85 17.15 18.05 18.05 17.45 2000.12.30 15.05 16.40 16.95 16.75 18.25 18.35 17.65 220011135 14.80 16.70 17.05 17.50 17.95 18.75 18.95 2400] 14.45 17.50 17.45 18.25 18.45 19.00 18.85 2600] 13.70 17.35 17.80 17.95 18.35 18.60 19.05 2800] 14.50 17.60 18.35 18.50 19.15 19.25 19.30 3000| 14.80 18.85 19.35 19.45 19.90 19.90 20.10 3200| 15.10 19.25 20.50 20.65 21.20 21.00 21.55 3400! 15.05 19.05 20.80 21.35 21.80 21.60 21.95 3600 14.75 19.40 21.35 21.90 22.05 22.15 22.35 3800 14.30 19.30 21.75 22.35 22.65 22.85 23.05 4000 14.00 19.00 21.70 22.15 22.70 23.35 23.60 4200 18.70 21.40 22.35 23.05 23.20 23.35 C. 6.3 Map Boundaries and Blanks The base fuel flow rate map shows a sudden peak in fuel flow at low RPM and high load. The engine is not meant to run in this regime: logging occurs. For the same reason, maps show blanks at higher throttle angles and low RPM. Maps also show blanks at low throttle angles and high RPM. this is the region of backfiring. IT IS NOT ADVISABLE TO RUN THE ENGINE OUTSIDE THE RPM REGIONS SHOWN. Maps stop at 80 degrees throttle: no significant differences were seen between the settings at 80 degrees throttle and those at WOT. Maps stop at 1200 RPM because the setup has a resonance at about 1000 RPM. The dynamometer is 99 not meant to run below 800 RPM. Maps stop at 4200 RPM because of dynamometer RPM and safety limitations. C.6.4 Base Spark and Fuel Maps in terms of Manifold Pressure and Cylinder Air Charge The air intake variable directly associated with the combustion process is the cylinder air charge mac. The engine load is strictlyproportional to the air charge. The aim of the control system is to set spark and fuel injection timing for a given air charge and engine RPM. Spark advance is used to set the engine torque (or mechanical power). Fuel injection sets the air to fuel ratio. The air to fuel ratio influences emissions in the exhaust as well as specific fuel consumption. The base timing maps given in Table 0.5 and Table 06 use throttle angle as a measure of engine load, assuming the cylinder air charge depends on throttle angle and RPM only. This approach is not entirely correct due to the action of the idle air control valve. The intake airflow is a function of engine RPM, throttle angle AND idle air control valve duty cycle. This means that for a given throttle angle and RPM, the cylinder air charge may still vary for different IAC valve duty cycles. It is therefor more appropriate to use the mean manifold pressure pm or the cylinder air charge mac as a mapping variable for engine load. Manifold pressure is the preferred variable since it can much more accurately be measured than the cylinder air charge (or mass airflow in the intake). For the running conditions of Table 0.5 and Table 0.6 (i.e. with the IAC valve actuated by the EEC), Table 0.8 and Table 09 give manifold pressure and mass airflow as a function of throttle angle and engine RPM. Elimination of the throttle angle 100 out of a combination of Table 0.8 and Table 0.9 with Table 0.5 and Table 0.6 yields maps for spark and fuel injection timing as a function of air charge or manifold pressure. These maps were not generated due to time constraints. Airflow and manifold pressure vary with environmental conditions (pressure p0 and temperature To). THE MAPS REPRESENTED WERE TAKEN AT: p0 = 96.3 kPa (C.3) To=297.6 K Dependency of the maps on environmental conditions can be avoided by expressing them in terms of dimensionless variables. If one assumes that the manifold temperature Tm is approximately equal to the environmental temperature To, a set of dimensionless variables is given by: —9— with 8", = 90° ref Pm pref with p”! = p0 m (0.4) _“withm =0.685- ”0 -A. ref c The constant requals 287 J/(kg K). m is the airflow for choked flow through the "f intake (minimum area A1) at wide-open throttle. For the current intake system on the engine, A; could be chosen equal to 1.338 E-3 m2 (inner diameter of the MAF sensor = 1 5/8”). Vc is the displaced volume of the cylinder and equals 0.4646 E- 3. For ease of comparison with the axes of the spark and fuel injection timing maps (Table C5 and Table 0.6) as well as to get a feeling for the absolute values of manifold pressure and mass airflow in the intake, maps were not 101 presented in dimensionless form. WHENEVER USING THE MAPS OF TABLE 08 AND TABLE 09, TAKE INTO ACCOUNT THE CHANGE OF THE MAPPED VARIABLES AND THE MAP AXES WITH THE ENVIRONMENTAL CONDITIONS (c.3) THROUGH EQUATIONS 0.4. A map for air charge can be derived from the mass airflow map through multiplication with the period of an intake stroke: m... = n,“ .1_29_ (0,5) RPM Mapped airflow and manifold pressure represent mean values only. Real airflow and pressure are fluctuating due to the intake pulses. Mean values were obtained in the following way. For manifold pressure, the mean voltage output of a manifold pressure sensor was calculated using the voltage averager of the digital oscilloscope. Mean voltage was then related to manifold pressure through sensor calibration. For mass airflow, the situation is much more complicated: mass airflow is very hard to measure directly. To measure mass airflow, fuel injector pulse width was adjusted until the HEGO sensor in the exhaust system showed stoichiometric combustion. Stoechiometry was defined as the operating condition for which the HEGO sensor switches between rich and lean voltage levels AND thereby stays rich as long as it stays lean. The injector pulse width at stoechiometry was recorded as a function of throttle angle and RPM. Fuel flow was calculated using (C.2). At stoechiometry, the mass airflow rate in the intake is approximately 14.6 times the fuel flow rate. Due to the nonlinear HEGO sensor voltage 102 characteristics as a function of air to fuel ratio, the measure for stoechiometry might be off by a constant factor. I 9000-10000 l80.00-90.00 I70.00-80.00 El 60.00-70.00 Manifold pressure ' . 05000-6000 [kPa] - . “Ell". I40.00-50.00 .llli:! “0.00-40.00 I . . 6 0 Throttle Angle [deg] Fig. 0.20: Manifold Pressure @ po= 96.3 kPa, To = 24.5 °C C. 6.5 Cold Start Enrichment During engine warm-up the base fuel flow rate of Table 0.6 is multiplied by a constant that depends on the elapsed time after startup was initiated, on the engine coolant (or block temperature) or on both. Cold start enrichment was not studied in detail. For a single test run at 1400 rpm and 10 % throttle, it was observed that cold start enrichment was applied up to a block temperature of about 140 °F, which was reached 3 minutes after startup. For the test run, Table 0.10 gives values for the cold start enrichment multiplier as a function of block temperature. 103 Table C.8: Manifold Pressure p. = f (RPM,0) mekPai I am RPM | 10 20 30 40 50 60 70 80 1200| 83.35 89.76 92.28 93.07 93.45 93.45 93.84 93.84 140017830 87.24 91.90 92.87 93.07 93.45 93.45 93.45 1600] 74.41 85.29 91.12 92.68 93.07 93.45 93.45 93.84 1800] 69.36 82.57 90.54 92.28 93.07 93.45 93.84 93.84 20001 64.32 79.86 89.57 91.90 93.07 93.45 93.84 93.84 220016121 77.91 88.79 91.51 92.68 93.45 93.84 93.84 240015810 76.36 87.62 91.12 92.68 93.45 93.64 93.84 2600I 56.15 74.81 86.85 90.74 92.28 93.07 93.45 93.45 2800] 53.25 72.48 86.07 89.95 91.51 93.07 93.07 93.45 300014955 69.36 84.32 89.18 91.12 92.68 92.68 93.07 32001 44.78 65.49 81.41 88.41 90.74 92.28 92.68 92.68 3400] 41.86 62.76 79.86 87.24 89.95 91.71 92.28 92.28 360013907 59.27 77.53 86.07 89.18 90.74 91.51 91.901 3800| 36.54 56.15 75.58 84.90 88.01 89.95 91.12 91.51l 4000] 35.06 53.82 74.03 84.13 87.62 89.95 90.74 91.12] 420013467 53.05 72.67 83.16 87.24 89.18 90.34 91.12] Table C.9: Mass Airflow the = f (RPM,0) iii, 9l°I [kg/hr] RPM 10 20 30 40 50 60 70 80 12001 50.69 55.96 1400] 56.40 65.50 67.46 68.59 1600] 60.72 73.62 76.05 78.42 80.03 80.94 81.91 81.72 1800] 64.78 81.29 85.73 88.44 89.87 90.82 91.69 91.01 200016848 88.68 96.55 99.96 101.22 102.56 103.29 103.03 2200] 70.59 94.84 106.36 109.68 111.00 112.52 113.59 113.03 2400| 100.80 115.17 118.93 120.38 122.11 122.98 122.59 2600I 104.51 120.50 125.99 127.14 129.26 130.07 130.19 28001 109.41 127.73 134.59 135.62 138.12 139.16 138.97 3000] 113.55 135.84 144.84 145.32 149.02 149.65 149.91 3200] 118.08 147.34 159.33 162.59 165.24 166.16 166.69 3400] 120.63 154.07 170.07 173.85 176.93 178.13 178.21 3600 123.52 162.62 181.21 186.43 190.15 193.07 192.58 3800| 125.53 171.68 193.40 200.95 206.09 206.59 208.89 4000] 127.60 177.11 202.37 210.76 216.52 218.64 219.87 4200] 180.31 210.32 219.45 225.72 228.47 229.47 104 Fig. 0.21: Mass Airflow @ p0: 96.3 kPa, To = 24.5 °C Table C.10: Cold Start Multiplier as a Function of Block Temperature (1400 rpm, 10% throttle) Tblock [°F] 85 J 89 96 100 108 114 125 132 140 multipliergcr 1.38l1.34 1.28 1.20 1.17 1.11 1.07 1.02 1.00 C.6.6 Air Charge Temperature Trimming of Fuel Injection Fuel injection maps are set to have the engine run at particular air to fuel ratio conditions dependent on engine RPM and engine load. The mapping entries are however dependent on the environmental conditions. Changes in environmental conditions will then cause changes in air to fuel ratio. A change in temperature is accounted for by means of the air charge temperature multiplier. Since manifold density varies inversely proportional to manifold (or intake) temperature, the same will be true for the mass airflow into the cylinder. Base fuel flow rates are then multiplied with a constant based on a measurement of the actual manifold 105 temperature Tm, with respect to the reference manifold temperature TmMAp for which the fuel map was calculated: multiplierACT = T3?” (C.6) m C. 6. 7 HEGO Trimming of Fuel Injection At low RPM and throttle angles, passenger car engines are normally tuned to run at low emissions and high mileage. Air to fuel ratios are then set near stoechiometry. Base injector flow rates may be a little off stoichiometric conditions. Also, environmental operating conditions may change, altering the air to fuel ratio. To compensate for these errors, at low RPM and throttle angle, the engine controller runs in HEGO feedback mode. In this control mode a signal from the HEGO sensor is fed back into the controller. The signal indicates whether the engine runs rich or lean. If the engine runs rich, the fuel pulse width is decreased until the HEGO indicates lean condition. From that moment on, the pulse width is increased again until the engine runs rich, and so on. The HEGO sensor continuously switches between rich and lean conditions as fuel pulse widths ramp up and down. The specific algorithm for the HEGO feedback could not be obtained from Ford. The following information could however be extracted through oscilloscope measurements: 1. The HEGO feedback has about 0.3 milliseconds worth of authority to change the injector pulse width 2. The HEGO feedback is only active in certain throttle-RPM regions (low throttle and low RPM). At high RPM and throttle, the engine runs rich and 106 HEGO is not active. This means that in these regions it was tuned to generate power instead of running efficiently. Table 0.11 gives measurements for the relative air to fuel ratio A as a function of RPM and throttle angle. The shaded regions indicate the load-speed domain in which the HEGO feedback was found to be activated (HEGO sensor voltage switching). Outside the shaded region, the HEGO sensor was not active. As can be observed from the table, this region primarily corresponds to rich conditions (A < 0.95). High values for lambda outside the shaded region are due to the base pulse width setting being close to stoechiometry: the HEGO feedback needs not to be active to yield stoichiometric combustion. Table C.11: Relative A/F Ratio .3. = (AMT/(Alli)“m,I as related to HEGO Feedback 6 107 C.7 Engine Startup and Shutdown Procedures C. 7.1 Engine Startup (using the Ford EEC) —L . Follow the safety check instructions of Appendix B.1 . Follow the pre-run check and running preparation instructions of Appendix B.2 Follow the dynamometer startup instructions of Appendix B.3 till step # 14. Pull out the emergency switch (yellow box mounted at the bottom of the dynamometer control panel) and turn on the fuel pump (manual operator panel switch up) to allow the fuel to pressurize and air bubbles to escape from the fuel lines. Fuel pressure on the gauge should show about 35-40 psi with the engine not running. The engine will have a rough start if this step is skipped. Push the emergency switch to disconnect power from the operator panel and turn on the ignition switch and the fuel pump switch on the operator panel (both manual switches up). Proceed with steps 15 and 16 of appendix B5 to bring the engine at high idle (1200 RPM) To fire the engine, pull out the emergency switch. Allow engine wann-up before continuing. For smooth warm-up, run the engine at about 10 % throttle and 1400 rpm. It will take approximately 3 minutes for the engine block to reach 140 °F and about 6 minutes to get up to steady temperature (190-195°F). The engine is warm if the thermostat opens: 108 the hose connecting the thermostat housing to the coolant valves will then be hot. C. 7.2 Engine Shutdown 1. Gradually remove the load on the engine (either throttle position or torque). 2. Allow the engine to “idle” by turning down the “Speed” knob until 1200 RPM (engine setup has a resonance at about 1000-1100 RPM). 3. Idle the engine for about 5-10 minutes to allow the oil to cool down to approximately 2009 F. 4. Push the emergency stop button (yellow box mounted at the bottom of the dynamometer control panel) to turn off the ignition and the fuel pump. 5. Follow the instructions of Appendix B.5 for dynamometer shutdown. 0.8 Remaining Tasks As for facility development, the following tasks remain. The exhaust pipe needs to be cut to size and welded together. Additional exhaust heat shields need to be put up in order to avoid melting of the coolant hose leaving the engine. The coolant hose entering the engine needs to be extended in order to keep it away from the muffler. The rotor of the exhaust fan needs to be welded onto its shaft to avoid loosening at high exhaust temperatures. The Cosworth |05460 Engine Control System ® has only been run in its manual control mode. In order to run the system in its more advanced table control modes, the base timing maps received from Ford need to be converted into the form required by the |05460. It is advisable to use the manifold pressure as a 109 measure for engine load instead of throttle angle or mass airflow. The internal |05460 system chip is currently set up to run off the manifold pressure sensor. In order to run the Cosworth system in table control mode, an emergency switch needs to be installed, since ignition and fuel injection cannot be shut off from the host program. The 12-volt line connecting battery power to the distributorless ignition box needs to be run through the emergency switch. The red jumper wire (which connects the internal voltage supply to the fuel injector power input) at the back panel of the Cosworth System will have to be run through the emergency switch as well. 110 APPENDIX D MAIN DOCUMENT DATA SHEETS This appendix lists the data used in the main document. Table D.l: Friction Torque =flRPM,H), refer to Fig. 6 Tr 9[°] [ij RPMI 10 20 30 40 50 60 70 80 1200| 12.2 11.8 1400L12.9 12.2 12.2 12.3 1600] 13.7 12.8 12.7 13 12.6 12.6 12.6 12.8 1800] 14.8 13.7 13.6 13.7 13.3 13.3 13.3 13.4 2000 16 14.8 14.5 14.8 14.1 14.1 14.1 14.3 2200] 17.2 16.2 15.6 15.6 15 15 15 15.4 24% 17.1 16.4 16.3 16 16 16 16.2 2600] 17.8 17.2 17.1 16.4 16.4 16.4 16.6 2800] 18.5 17.8 17.7 17.4 17.4 17.4 17.7 3000] 19.5 18.9 18.9 18.3 18.3 18.3 18.4 3200L 20.7 19.8 19.9 19.2 19.2 19.2 19.5 3400] 21.3 21 20.8 20.3 20.3 20.3 20.5 3600I 22.5 21.9 22.1 21.8 21.8 21.8 21.7 3800] 23.5 23 23.2 22.7 22.7 22.7 22.7 40001 23.8 23.5 23.9 23.3 23.3 23.3 23.9 4200 25 24.8 24.5 24.5 24.5 24.5 111 Table 0.2: Gross Indicated Torque =flRPM,€), refer to Fig. 7 (@ 97.1 kPa, 24.5 °C) Ti 9l°I [Nm] RPMI 10 20 30 40 50 60 70 80 1200I87.3 96.2 1400|86.5 99.4 10131025 1600| 81.8 97.9 101.7 104 104910931091 109.5 18% 77.3 96.4 102.6 105.3 106.3 109.9 109.5 109.8 2000] 73.3 94.4 103.7 107.1 107.6 110.9 110.5 111 2200| 67.1 91 104.7 106.1 106.4 112.5 112.2 112.4 2400| 88.2 104.3 107.4 108.8 112.3 112.1 111.3 2600] 86.4 102.5 105.8 107.4 110.9 110.7 110.2 2800i 86.5 101.8 105.9 107.4 110.6 110.8 110.4 3000] 84.8 101 10651081 11191118 111 3200] 83.5 102 109.7 111.4 115.5 115.8 115.8 3400] 79.8 102 110.4 112.9 116.8 117.6 117.4 3600] 77.3 100.5 111.7 114.8 119.5 120 119.6 3800] 74.6 100.2 112.8 116.1 121.3 122.1 121.9 4000i 70.3 97.3 110.9 114.5 119.5 120.8 121.4 4200] 93.3 108.4 112.9 118.5 119.7 119.9 Table D.3: Mechanical Efficiency =flRPM,9), refer to Fig. 8 nm I 61°] RPMI 10 20 30 40 50 60 70 80 1200l0.86 0.88 1400|0.85 0.88 0.88 0.88 1600] 0.83 0.87 0.88 0.88 0.88 0.88 0.88 0.88 1800|0.81 0.86 0.87 0.87 0.87 0.88 0.88 0.88 200010.78 0.84 0.86 0.86 0.87 0.87 0.87 0.87 2200| 0.74 0.82 0.85 0.85 0.86 0.87 0.87 0.86 2400] 0.81 0.84 0.85 0.85 0.86 0.86 0.85 2600] 0.79 0.83 0.84 0.85 0.85 0.85 0.85 2800] 0.79 0.83 0.83 0.84 0.84 0.84 0.84 3000| 0.77 0.81 0.82 0.83 0.84 0.84 0.83 3200] 0.75 0.81 0.82 0.83 0.83 0.83 0.83 3400| 0.73 0.79 0.81 0.82 0.83 0.83 0.83 3600] 0.71 0.78 0.80 0.81 0.82 0.82 0.82 3800| 0.68 0.77 0.79 0.80 0.81 0.81 0.81 4000] 0.66 0.76 0.78 0.80 0.81 0.81 0.80 42001 0.73 0.77 0.78 0.79 0.80 0.80 112 Table D4: SAI Multiplier, refer to Fig.9 (SA-MBT in ° crank) SA-M BT SAI SA-MBT SAI -25.5 0.695 -10.5 0.949 -24.5 0.720 -9.5 0.958 -23.5 0.740 -8.5 0.966 -22.5 0.764 ~7.5 0.974 -21.5 0.786 -6.5 0.980 20.5 0.800 -5.5 0.986 -19.5 0.820 -4.5 0.990 -18.5 0.843 -3.5 0.989 -17.5 0.859 -2.5 0.995 -16.5 0.875 -1.5 0.997 -15.5 0.891 -0.5 1.000 -14.5 0.901 0.5 1.000 -13.5 0.916 1.5 1.000 -12.5 0.926 2.5 0.998 -1 1.5 0.939 3.5 0.997 Table 0.5: AFI Multiplier, refer to Fig.10 A AFI it AFI it AFI AFI AFI 0.685 0.675 0.763 0.773 0.861 0.889 0.987 0.997 1.156 0.989 0.69 0.68 0.768 0.779 0.867 0.897 0.995 0.998 1.168 0.991 0.694 0.686 0.773 0.786 0.874 0.904 1.004 1.001 1.180 0.986 0.698 0.691 0.779 0.792 0.881 0.911 1.013 1 .003 1.192 0.978 0.702 0.696 0.784 0.799 0.887 0.917 1 .022 1 .009 1 .205 0.948 0.707 0.702 0.789 0.806 0.894 0.924 1.031 1 .005 1.218 0.947 0.711 0.707 0.795 0.813 0.901 0.93 1.041 1 .008 1.231 0.952 0.715 0.713 0.801 0.819 0.909 0.937 1.05 1.01 1 .244 0.934 0.72 0.719 0.806 0.826 0.916 0.944 1.06 1 .008 1 .258 0.911 0.725 0.724 0.812 0.832 0.923 0.952 1.07 1.011 1 .272 0.906 0.729 0.73 0.818 0.838 0.931 0.959 1.08 1 .009 1 .286 0.865 0.734 0.735 0.824 0.845 0.938 0.965 1.09 1 .005 1.301 0.855 0.739 0.742 0.83 0.851 0.946 0.972 1.101 1 .006 1.316 0.823 0.743 0.749 0.836 0.859 0.954 0.976 1.111 1.004 0.748 0.755 0.842 0.866 0.962 0.983 1.122 0.753 0.761 0.848 0.873 0.97 0.985 1.133 0.998 0.758 0.767 0.854 0.88 0.978 0.99 1.145 0.994 113 Table 0.6: In-Cylinder Fuel Mass, refer to Fig.13 mfc 9 [°] 1 0 20 30 40 50 2.415E-05 2.746E 2.218E-05 2. 2. . 3.086E-05 2. 3.122E-05 1 3.068E-05 3.1 3.140E-05 3.417E-05 2.549E-05 3.757E-05 2. . 3.801 2.41 3.7 3.909E-05 2.361 3.256E-05 3. 3.91 Table D.‘7: Indicated Fuel Conversion Efficiency =f(RPM,0), refer to Fig. 14 m I 9[°] RPM[ 10 20 30 40 50 60 70 80 120010.337 0.350 140010.347 0.351 0.345 0.353 160010.357 0.360 0.367 0.353 0.349 0.356 0.345 180010.358 0.361 0.362 0.355 0.352 0.345 0.343 0.357 200010.345 0.358 0.360 0.359 0.365 0.344 0.341 0.357 220010.344 0.352 0.357 0.353 0.345 0.355 0.338 0.335 24001 0.350 0.338 0.349 0.337 0.344 0.333 0.334 2600] 0.363 0.335 0.337 0.339 0.342 0.337 0.327 28001 0.342 0.328 0.327 0.329 0.326 0.325 0.323 30001 0.328 0.303 0.311 0.313 0.317 0.317 0.311 32% 0.316 0.299 0.301 0.304 0.307 0.310 0.302 34001 0.303 0.302 0.299 0.297 0.301 0.306 0.300 3600] 0.300 0.292 0.294 0.295 0.304 0.304 0.300 38001 0.299 0.293 0.291 0.292 0.301 0.300 0.297 4000] 0.288 0.289 0.287 0.290 0.295 0.290 0.288 4200] 0.282 0.285 0.284 0.288 0.289 0.288 114 Table 0.8: In-Cylinder Fuel Mass at Stoechiometry, refer to Fig.15 mt. 9 [°] RPM 10 20 30 40 2.41 1 2. 2.300E-05 2.671 2.751 2. 2.166E 2.627E 2.71 2.798E-05 2.055E 2.578E-05 2.71 2.805E-05 2.880E 1.955E 2.531 E 2. 2.853E-05 1 2.461 2. 2.920E-05 2. 2.829E-05 2.904E-05 2.295E 2.646E-05 2.766E 2.231 E 2.7 . 2.816E 2.161 E-05 2. . 2.836E-05 2.1065 2.025E 2.855E-05 2.971 1 .959E 3.01 1 .886E 2.905E-05 1.821 2.888E-05 For Fig.16, refer to Table 0.11. Table D.9: Cylinder Air Charge, refer to Fig.17 mac 9 [°] R 1 0 20 30 40 50 60 4 . 4.21 4 4.205E 4.024E 4.1 4.274E 4 4.1 4.263E 4.1 4.240E 4.039E-04 4 4.1 4 4 4.1 1 1 3.77 4 4 4.140E 4.1 4 4 4 4 1 1 . 4 1 1 3. 4.1 4.337E .31 4.402E 2.860E-04 3.765E-04 4.1 2.753E 3. 4 4. 4.520E 2.659E 4.217E-04 4.391 4.512E 4.17 4 4- 115 Table D.10: Calculated MBT =flRPM,0), refer to Fig. 18 MBTI 91°] RPMI 10 20 30 40 50 60 70 80 12001 25.037 23.497 14001 27.632 24.805 24.301 24.053 16001 30.205 26.516 25.928 25.439 25.120 24.939 24.753 24.789 1800132164 28.262 27.403 26.946 26.711 26.552 26.416 26.521 20001 34.019 29.946 28.731 28.257 28.080 27.924 27.838 27.868 22001 33.458 29.507 28.126 27.769 27.631 27.489 27.392 27.442 2400] 28.909 27.609 27.305 27.190 27.066 27.006 27.033 26001 27.793 27.089 26.758 26.688 26.561 26.513 26.506 28001 27.132 26.184 25.870 25.823 25.709 25.663 25.672 3000] 26.039 25.193 24.899 24.884 24.765 24.748 24.741 32001 26.129 24.900 24.571 24.494 24.433 24.412 24.399 3400] 26.124 24.765 24.371 24.294 24.238 24.216 24.215 36001 27.428 25.731 25.160 25.019 24.933 24.865 24.876 3800| 30.167 27.840 26.870 26.568 26.383 26.365 26.282 40001 32.958 30.142 28.708 28.245 27.971 27.870 27.812 42001 32.626 30.654 30.003 29.639 29.480 29.422 Table D.ll: Stoichiometric Fuel Conversion Efficiency =flRPM,9), refer to Fig. 19 ntI 9 [°] RPM] 10 20 30 40 50 60 70 80 120010.343 0.350 140m 0.357 0.355 0.351 0.354 1600I 0.361 0.361 0.366 0.356 0.352 0.361 0.354 0.360 1800 0.361 0.361 0.364 0.359 0.356 0.360 0.355 0.362 2000 0.355 0.359 0.362 0.361 0.364 0.357 0.354 0.361 220010.349 0.355 0.362 0.357 0.352 0.365 0.357 0.359 24001 0.353 0.358 0.359 0.357 0.363 0.359 0.358 26001 0.364 0.362 0.359 0.361 0.366 0.363 0.361 28001 0.363 0.366 0.362 0.364 0.369 0.366 0.366 30001 0.367 0.370 0.363 0.368 0.371 0.370 0.367 32001 0.374 0.368 0.365 0.363 0.371 0.369 0.369 34001 0.374 0.374 0.367 0.367 0.373 0.372 0.373 36001 0.375 0.372 0.370 0.370 0.376 0.371 0.372 38001 0.377 0.370 0.370 0.366 0.372 0.374 0.369 40001 0.368 0.367 0.367 0.362 0.367 0.369 0.370 42001 0.364 0.361 0.361 0.369 0.367 0.367 116 038.0 038.0 038.0 380.0 880.0 038.0 808.0 _8«4 038.0 0300.0 038.0 «38.0 0300.0 0300.0 088.0 088.0 «88.0 0880—88 8800 038.0 038.0 308.0 038.0 038.0 808.0 880.0 «88.0 088.0E8 $08.0 38.0 038.0 038.0 «38.0 0800.0 088.0 308.0 «800.0 8080—88 38.0 038.0 038.0 «38.0 «38.0 380.0 088.0 088.0 808.0 88.0 0880—83 0380 0300.0 «38.0 «38.0 .3000 038.0 880.0 088.0 808.0 308.0 ‘88 «300.0 38.0 038.0 038.0 038.0 038.0 880.0 088.0 308.0 «88.0 _800 «300.0 38.0 038.0 038.0 080.0 0080.0 088.0 088.0 308.0 _80« 38.0 38.0 038.0 038.0 038.0 088.0 880.0 088.0 308.0 _08« «38.0 «38.0 380.0 38.0 38.0 038.0 088.0 308.0 83 «38.0 «38.0 38.0 38.0 38.0 0300.0 088.0 380.0 308.0 «080.0 880.0 088.288 «300.0 «38.0 .380 38.0 038.0 0300.0 088.0 308.0 308.0 «88.0 808.0 _08« «300.0 38.0 038.0 038.0 0080.0 880.0 0080.0 088.0 808.0 880.0 89 «38.0 038.0 038.0 038.0 088.0 088.0 880.0 880.0 «88.0 J08. 038.0 038.0 038.0 038.0 088.0 0080.0 880.0 _83 0080.0 088.0 088.0 _8«F 8 «0 .0. 00. 0.0 8 8 00 mu 0« 8 00 _ Sam 3%: SQ «« .3... 8 502 .15 .245? 0326 .5. 50008 "2.0 0.8... 117 REFERENCES 118 References Ahlstrand, A., Haynes, J .H., “Ford Escort and Mercury Tracer Automotive Repair Manual,” Haynes North America, Inc, Newbury Park, CA, 1996 Chang, R.T., “A Modeling Study of the Influence of Spark Ignition Engine Design Parameters on Engine Thermal Efficiency and Performance,” M.I.T. Department of Mechanical Engineering, Sc.M. thesis, 1988 Dobner, D.J., “A Mathematical Model for Development of Dynamic Engine Control,” pp.373-381, SAE Paper No. 800054, SAE Transactions, 1980 Fitzpatrick, T., “Engine Start-up”, Hulett Road Engine Research Lab, 1995 Hempson, J .G.G., “The Automobile Engine 1920-1950”, SAE paper No. 760605, vol. 85, 1976 Heywood, J .8, “Internal Combustion Engine Fundamentals”, McGraw-Hill, New York, 1988 Huang, R.W., Velinsky, S.A., “Spark Ignition Engine Modeling for Vehicle Dynamic Simulation”, DSC-Vol. 52, Advanced Automotive Technologies, pp. 369-378, ASME, 1993 Kamopp, D.C., Margolis, D.L, Rosenberg, R.C., “System Dynamics: a Unified Approach,” John Wiley & Sons, Inc., New York, 1990 Moskwa, J.J, Hedrick, J .K., “Automotive Engine Modeling for Real-Time Control Applications, ” Proc. of the 1987 American Control Conference, 1987 Moskwa, J .J , Hedrick, J .K., “Modeling and Validation of Automotive Engines for Control Algorithm Development,” Paper presented at the Winter Annual Meeting of the American Society of Mechanical Engineers, San Francisco, 1989 Powell, B.K., Cook, 'JA, “Nonlinear Low Frequency Phenomenological Engine Modeling and Analysis”, Proceedings of the American Control Conference, pp. 332-340, 1983 Powell, J.D., “A Review of IC Engine Models for Control System Design”, IFAC 10th Triennial World Congress, pp. 235-240, Munich, 1987 Reliance Electric Industrial Company, “Dodge ® Engineering Catalog, Vol. 1.1,” Greenville, SC, 1993 Ribbons, W.B., “Understanding Automotive Electronics”, pp.150-152, Butterworth- Heinemann, Wobum, MA, 1998 Servati, H.B., Delosh, R.G., “A Regression Model for Volumetric Efficiency,” SAE Paper No. 860328, 1986 Tennant, J.A., Giacomazzi, R.A., Powell, J.D., Rao, H.S., “Development and Validation of Engine Models via Automated Dynamometer Tests”, SAE Paper No. 790178, 1979 119 HICHIGAN STATE UNIV. 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