H .‘l l HHIHH 144 522 __THS THE DESIGN AND TESTING OF AN ELECTRIC UNDERFLOOR CHICKEN BROODER Thesis for II“: Degree of M. S. MICHIGAN STATE UNIVERSITY Frank Donald Borsenik 1958 I ilbilwlb. Earle!!! II 2.? TE 1510‘ AND TESTING OF AN ELEOIEEC UNIEIFLOOR CHICKEN BEDODER FMNK DONALD BOFBENIK AN ABSTRACT Submitted to the College of Agriculture of Michigan State University of Agriculture and Applied Science in partinl fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of tgrlcultunl Engineering 1958 \\ ~74 I'm; ., I a ”I Approved LL] - 5:57:12 ICCaCt If ' i v—' 5...”, ABSTRACT Breeding chickens with electrical energy is very popular. There are any reason for this popularity; the electric breeders are readily portable; electricity has no by—preducts of combustion such as make, carbon dioxide, carbon monoxide and water; electric breeders reduce fire hazards; and the con- version ef electricity to heat is 100 per cent efficient which provides for ecenaicel operation. Haven’type breeders are normally designed for conduction and convection heat transfer and infrared lamp breeders are designed for radiation heat transfer. The energ requirements for breeding chickens were reported by Mitchell and Kelley (1933). Their publications were based primarily on conduction and con- vectien heat transfer. Seeger and oliver (1951) combined their research data with the data reported by Mitchell and Kelley and reported radiant heat transfer requirements for chickens. Many types of radiant breeders have been designed. Radiant brooding with infrared breeder lamps is an accepted method for northern and southern United states conditions. However, con-- crete slab with electric resistance Hires, electric panel and - electric hover breeding are net advantageous for conditions that exist in the northern United States. The purpose of this experiment was to design and test an underfloor electric chicken breeder for conditions that endst in the northern united states. The designed underfloor electric breeder transferred over 90 per cent of the heat by convection and conduction. Less than 10 per cent of the heat was transferred by radiation. Many con- aercial radiant type breeders of similar design transfer heat in the same proportions. They are not true radiant heat breeders. Three groups of chickens were raised on the designed under- floor breeder, sometimes called a heat slab. The breeder floor was the heat source, providing a direct contact between chicken and the heat. Also, three groups of chickens were raised under infrared breeder lamps for comparison. The infrared lamp breeder provided the standard of measurement. A comercial radiant floor breeder was used in a late spring breeding test. This breeder was actually a conduction and con- vection breeder. ‘ This breeder was used in one test only. The results were not valid but are recorded with other vital results. The designed heat slab breeder indicated: lower electric energ consumption, reduced chicken mortality, constant tampon- ture control, and capacity for holding heat and releasing this heat during power interruptions. There was no consistent differ- ence in chicken growth rates between the designed heat slab breeder and infrared lamp breeders. THE DESIGN AND TESTING OF AN ELECTRIC UNUERFIOOR CHICKEN BROODER BY FRAMC DONALD BORSENIK A THESIS submitted to the college of Agriculture of Michigan state University of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Agricultural mgineering 1958 ACKNWIEDGMENTS The author erqaresses his sincere appreciation for the counsel, guidance, and interest of Professor D. E. Wiant, under whose super- vision this work was done. He is also indebted to Dr. A. w. Farrell, Head of the Department of Agricultural mmeenng, Michigan state University, and to Dr. H. C. Zindel, Head of the Poultry Husbandry Department, Michigan State University and to the Michigan committee on Film]. Electrifica- tion, D. E. Hunt, chairman, Department of Agricultural Ergineering, Michigan State University, for their support which made it possible to carry out this investigation. Appreciation is expressed to Dr. D. P. Brown, Professor J. A. Davidson and Dr. c. W. Hall for their sympathetic understanding and helpful suggestions during the course of the study. Professor J. A. Davidson was especially helpful on many questions because of his particular experience and qualifications with regard to a problem of this nature. Thanks are also extended to the Detroit Edison company, Detroit, Michigan, for supplying the materials of construction for the heat slab breeder, and to Radiant Products, Inc., Monroe, North carolina for the breeder used in the second brooding test. FRANK DONALD BORSENIK candidate for the degree of Master of Science Final Examination; Dissertation; The Design and Testing of an Electric Underfloor Chicken Breeder outline of Studies; Major Subject; Agricultural Engineering Minor subject; Pmsics Biographical Items; Born; October 19, 1933, Saginaw, Michigan Undergraduate studies; Michigan state University, 1951-1955, BSAE, 19 55 Graduate Studies; Michigan State University, 1955-1958 Experience: The candidate worked as an engineering aid in Michigan and Indiana during his undergraduate studies, 1952-1955, on work concerned with I the development of a mechanical cucumber harvester. In 1955 he accepted a graduate assistantship in the Department of Agricultural Engineering, Michigan State University. In January, 1956, he accepted an appointment of research assistant, Department of Agricultural Bigineering, Michigan State University; the work concerned radio and television programs in rural electrification and research in the same field. In October, 195?, he accepted an appointment as instructor in the Department of Hotel, restaurant, and Instihruenal Managanent, Michigan state University, teaching mechanical equipment and doing research in the food service field, the position held at the present tines Huber-ship in Organizations: American Society of Agricultural Engineers 11 TABLE OF'CONTENTS P880 IMWUCTIG 0.0.0.....0..OOOOCOOOOOOOOOCCOCOOOOOOOOOOOCOOOOO 1 wJEcrI‘VES 00.000.000.000...0.00.00.0000000000000000000.0...‘ h mm OF LITEMTURE OOOOOOCOOOOOOOOOOOOOOOOOOOOOOIOOOQOOOOO. 5 Rmmmnmmm.mmmmmmmmmmmmfl5 DEIGNING AND TESTING THE HEAT SLAB BROODER.............. 15 FIRST TRIAL ammo TEST. 18 SECOND TRIAL BRoonINc_TEST............................... 18 THIRD TRIAL BROODING TEST... 18 P‘ESUIITS .OOOOOOOOOOCO0.0.0.0....000000000OOOOOOOOOOOOOOOOOOOO 23 ENERGY MEASUREMENTS OF THE UNDERFLOOR.TYPE BROODER....... 23 RESULTS OF THE FIRST TRIAL EROODING-TEST................. 27 RESULTS OF THE SECOND TRIAL BRDODING'TEST................ 29 RESULTS OF THE THIRD TRIAL BROODING TEST h2 DISCUSSION OF RESUBTS ....................................... AS 51mm 00.......00....OOOOOOOOOOOOOOOOOO0.0. OOOOOOOOOOOOO... 57 WNW 0.0.0.00000000004000OOOCOOOOOOOOOOOOOOOOO0.0.0.... w OOQO‘. ) I ' 4 0 v - I . w . e . e n . . Vvaqe v o g 0 C O u 1 I v n I e a O u v C C o a I Q g e «holy Q... Q Q I Q . ‘ O . . u D I I e a Q n o a o e . I O Q . U I D 0 C . ' odhv-IO e e e e v 0 v e v o . . ~ - I I Q 9 o - e ¢ 0 w u a O I I 'OOI'QIQQ.... '1...‘ O O O I I “ A I ' 0 I Q .I.’. DOI‘. Q 0 e i I o C O 0 Table 1. 2. 3. 5. 6. 7. 9. 10. 11. LIST OF TABLES comparison of heat costs and feed efficiency flor‘VtriouB ”Bthoda Of broadina eeoeeeeeeeeeoeeeeeeeee Design wattage and actual wattage of various circuits for the undgrfloor chicken broader; Band temperature 193 F eeeeeeeeeeeeeeeeeeeeeeeeoooeeee The measurement of heat above the heat slab broader Vith.mercury’thermometers eeeeeeeeeeeeeeeeoeee Average hourly temperatures under three hovers placed over the heat slab brooder. The 900 watt circuit was in operation and the brooder thermostat “‘8 set ‘t 90°F eeeeeeeoeeeeeoeeeeeoeoeeeee Chicken mortality, feed conversion rates and electric energy consumption results of the first trial brooding test eeoeeeoeoeoeeeooeeeeeeeoeoee Iron-constantan thermocouple locations and the mean temperatures at these locations for the second trial brOOding teSt 0000.0000000000000000000000 Kilowatt hours used for brooding for three brooders, the second trial brooding test ............. Chicken mortality with three brooders, the second brooding tGSt oeeoeeoeeeeeeeoeeeooeeooeooooooee Feed conversion rates with three brooders, the B.COHd.brOOding test 0000000000000000.0000...00000000O Male and female chicken mean weights and the standard deviation of these mean weights for the chickens raised under three brooders, the second brOOding test eeeeeeeeeoeooeeeeeoeeeeeeeooooooo Chicken mortality with infrared lamp broader and the designed heat slab, for the third brood- ing test eee0000000000000000000000...eeeeeeeeeoeeeeeee iv Page 2h 25 27 29 3O 31 ha .A'OI “L“ 48 SAND " hue" I/4'MASONITE '" .. (2 INSULATION BATTS FIGS. HEAT SLAB CONSTRUCTION FOR A 250 CHICKEN PORTABLE BROODER SCALE: I'= I'O" HIGHLY REFLECTIVE SUR FACE ,5 g /// §\\\ /’ \\ / \\\ I // \\ II // \‘\\ 30 r - "I I e—cuzAR PLASTIC '7- 4s" lflNGES HANDLE he / .. L_;___________Ei.r I I/4"PLYWOOD : I L. : I I I ‘V 1 l I Ié 48" a» FIG.6. HOVER FOR PORTABLE HEAT SLAB CHICKEN BROODER SCALE:F=Id' .18 method for measuring radiation or temperature under the hover. First Trial Brooding Test The first brooding test was conducted to find if the heat slab broader would maintain desirable brooding conditions. one hundred and sixty eight chickens were placed on the heat slab broader and a similar number under an infrared lamp broader in separate brooding houses, April, 1957, Figs. 7 and 8. The criteria of this test were, hourly temperature measure- ments, electric energy consumption, chicken mortality and total feed conversion ratios. second Trial Brooding Test The second test was conducted with three types of hover brooders; infrared broader lamps under a wood hover, Fig. 9; the heat slab broader, Fig. 10; and a North Carolina commercial heat slab broader, Fig. 11 and 12. The criteria were: temperature control; electric energy consumption; feed conversion ratios; and chicken mortality. Two hundred and fifty chickens were placed under each broader. Third Trial Brooding Test A third test was conducted to find if a statistical signi- ficant difference existed between the weights of male and female chickens. The male chickens were kept separate from the female chickens throughout the test. Two brooders were used, infrared lamp broader and the heat slab broader. Sixty chickens of each sex were placed under each broader. The criteria were feed con- version rates and chicken mortality. l9 I Infrared lamp broader, first and third trial brooding test. Fig. 7. « a . - .‘ . _ {«' ; \ ‘1‘. ‘2’ - . ,‘ fl -. ,n'; . _‘ I ' “fi mm. x .,- - - raw. . , “a .-o‘ .-. _ - «of ._ v’ ‘e . ." . o ‘ -—‘—. Fig. 8. Designed heat slab broader, first, second and third trial brooding test. Fig. 9. Infrared broader lamps with a wood hover, second trial brooding test. .1 i --e ~ "-5“ ~.-. Fig. 10. Designed heat slab broader showing the clear plastic sides of the hover. as (,L .o._ ..._ .348 meno> ON. .323 nmm.>to a bdhmOZm—wzh Fig. 12. Radiant Products heat alab broader, used in the second trial brooding test. 22 HIBU'L'IS Insults of Enggy Measurements of the Underfloor Type Broader A 16 square foot broader was designed according to the principles established by Oliver and Seeger, Fig. 3. Assuming a law room temperature of 10°F and referring to Mitchell's results, Fig. 2, the projected area of chickens, it was calculated that a 900 watt infrared output would supply heat for 267 chickens, assuming 100 per cent efficiency. Calculations: 900 watts/hr. x 3.1413 Btu/watt = 3081.7 Btu/hr. A five day old chicken has a projected area of five square inches, Fig. 2. A five day old chicken in a 10°F room requires 2.3 Btu/inz/hr. Fig. 3. s in2/chicken x 2.3 Btu/inz/hr .-. 11.5 Btu/hr/ch'r cken Btu/hr : 3081.7 - 267 chickens, capacity of a Rafi/chicken 'II'S". 900 watt heating circuit The next step is to calculate the required surface area of the broader. The surface area should provide 2.3 Btu per square inch per hour. Btu/hr 2 = 3081.7 = 13110 in2, required surface area WE- in "2'23" / of the broader to provide 2.3 Btu/inz/hr. 23 The heating circuit in the heat slab broader required an area of 114141; square inches, this provided a heat. output of; Btu/hr :: 3081.7 I 2.11; Btu/inz/hr, which is Slightly 1888 “—2- 1m- than the desired amount. The heating circuit was centered on the center of the heat slab. The designed heat slab broader, Figs. 5 and 6, was heated with a nickel chronium resistance wire. The cold resistance of the wire was 0.163 ohms per foot. circuits of 200, 300 and 100 watts were installed in the underfloor broader. The heating cable was covemd with one half inch of sand to retain heat. Table 2 shows the actual wattages of the circuits as tested by a wathneter. TABLE 2. DESIGN WATTACE AND ACTUAL WATTAGE OF VARIOUS CIICUITS FOR THE UNDEBFLOOR CHICKEN BROODER! SAND TEMPERATURE 193°? DESIGN WATTACE ACTUAL WATTAGE 200 195 300 225 too ms 500 A15 600 585 700 615 900 780 25 Mercury thermometers were used to find the heat pattern above the heat slab when no hover was used, Table 3 shows the temperature pattern. TABLE 3. THE MEASURH‘ENT OF HEAT ABOVE THE HEAT SLAB BIDODER WITH MEIEURI TIERMOMETEIE WATTAGE OF HEAT mmwns AT THE FOLLONING DISTANCES 1200M CImUI'r SLAB ABOVE THE HEAT SLAB SURFACE °F SURFACE 1a 2w 3» ha 5» 6n °F 200 63.0 50.0 119.5 50.0 119.0 119.0 119.0 116.5 300 66.0 53.5 52.0 53.0 51.0 51.0 51.0 116.5 1100 77.0 53.5 52.5 53.0 51.5 50.5 50.5 116.5 600 87.0 514.0 51.0 52.5 50.0 50.0 119.0 110.0 900 82.0 115.5 113.5 112.0 1.1.5 10.5 38.5 27.0 An mpley radiation meter was used to determine the total infrared radiation output of the heat slab. The heat slab was marked off into six inch squares and with the meter connected to a potentiometer, readings were taken for the different wattage circuits. with the 500 watt circuit in operation the Btu output was 56.59 Btu per hour. Assuming 100 per cent efficiency for radiant heating the following calculation was made; 26 0.1.15 kw * x 31.13 Btu/kw/hr z 1h16.h0 Btu/hr. * The 500 watt circuit has an actual wattage of 1115 watts, see Table 2. The heat slab was found to be h per cent efficient for radiant heating. 1 Efficient -_.- Btu outputéhr r 100 = 56.59 : 11.00% B npu 111167110 The Eppley radiation meter was also used to measure the heat output of General Electric infrared broader lamps ; they were found to be 35.9 per cent efficient. A plastic type filter on the radiation meter filtered out part of the infrared spectrum. The readings were invalid as they existed because the filter could not be removed without partially destroying the meter. Three heat traps were used to test the effectiveness of the heat slab as a heat source for a hover type broader. The traps were; clear plastic; clear plastic with an aluminum sheet on the top; and a wooden hover. Iron-constantan thermocouples connected to a Brown recording potentiometer were used to record hourly - temperatures under the various hovers. Table 11 shows the results. The electric circuits were de-energized and the temperatures were taken under the hover with respect to time. Figure 13 shows the temperature versus time graph of the clear plastic hover with aluminum top which was selected as a desirable and efficient type hover. The selection of the clear plastic hover with alumina top was based on chicken visibility, heat retention capacity, desirable under-the-hover temperatures and the light weight con- struction of the hover. 27 TABLE 1:. AVERAGE HOURLY mssmrunss UNDER THREE 110va PLACED OVER THE HEAT SLAB BROODER. THE 900 mm CIRCUIT WAS IN OPERATION AND THE BROOnER THERMO- STAT WAS ssr AT 90°F. IDVER AVERACE mm AVE RAGE HEAT 6" ABOVE HEAT HOUTS TD’IPERA'NIE SLAB SURFACE SLAB SURFACE OPERA“r O F TEMPERATURE AVERAGE Timt TION o __ OF PERATUREL F __ mar Plastic 35 115 83 116 Clear Plastic with Aluminum - Sheet Top 32 122 82 20 wood 32 122 95 211 A bimetallic thermostat incased in plastic was used with the broader. It was wired in series with the 1100 watt circuit. The range of the thermostat was 60°F varying from 1.0 to 100°F. The accuracy of the thermostat was i 301?. It was set directly on the heat slab surface. A finger control dial provided easy operation and control. Results of the First Trial Brooding Test A three week trial brooding test was conducted April 3 through April 23, 1957 to observe chicken behavior under the hover of the electric heat slab breader and compare it with the behavior of a corresponding number of chickens under an infrared lamp broader. the hundred and sixty eight chickens were used for each breeder. °F TEMPERATURE. (D / a; \ N\ \ 60 -\ \\ \ 50 K 40 O I 2 3 4 5 6 7 s 910 HOURS A- SURFACE TEMPERATURE OF HEAT SLAB 8-6 IN. ABOVE SURFACE OF HEAT SLAB C- I IN. ABOVE SURFACE OF HEAT SLAB FI'G.|3. TEMPERATURE GRADIENT ABOVE THE HEAT SLAB. 900 WATT CIRCUIT OFF AT "0" HOUR. ROOM 20°F The primary result in this test was that the heat slab brooder was found to be suitable for the brooding of chickens. The data collected was of minor importance. Iron-constantan thermocouples were used with a Brown recording potentiometer for measuring hourly temperatures. The positions of the iron-constantan thermocouples were varied to find the most critical temperature locations under the brooders. Table 5 shows the chicken mortality, feed conversion rates and electric consumption. TABLE 5. CHICKEN MORTALITY, FEED COIUIRRSICN RATES AND ELECTRIC ENERGY CONSUMPTION RESULTS OF THE FIIBT TRIAL BROODIN G TEST HEAT SLAB BROODER INFRARED LAMP BmODER Chi cken Mortality 1.19% 5.98% Feed conversion Rates 2.08 lb feed 2.17 lb feed I5 gain 11 Electric Energy Consumption 1.365 kwh/chicken 2.070 kwh/clricken Rasults of the Second Trial Brooding Test A six week brooding test was conducted April 23 through May 27, 1957. The three types of brooders used in the second test are shown in Figs. 9, 10 and 12, infrared broader lamps under a wood hover, the heat slab broader and a commercial broader, respectively. No hundred and fifty chickens of various breeds were placed under each broader in separate 10 ft. I 12 ft. broader houses. Table 6 shows the location of the iron—constantan thermocouples whidr were used to obtain hourly temperature measurements. 30 TABLE 6. IRON-CONSTANTAN TRERMOOOUPLE LOCATIONS AND THE MEAN TEMPERA‘IUIES AT THESE LOCATIONS FOR THE SECOND TRIAL BROODING TEST MEAN TEMPERA- LOCATION ' TUBE, °F Broader House with the Infrared Broader Lamps Under a wood Hover a. Approximate center of the broader house 69.39 b. On the broader house floor under the litter 6h.79 c. ‘Under the hoverIand six in. above the litter 98.51 (1. Under the hover and 12 in. above the litter 1011.57 Broader House with the commercial Broader ‘ 8.. Approximate center of the breeder house 66.1.15 b. on the broader house floor under the litter ' 63.86 c. On the broader house floor under the heat slab 911.23 d. Under the hover and six in. above the heat slab 8b. 76 e. Under the hover and 12 in. above the heat slab 86.211 f. 0n the top of the heat slab hover 79.62 Breeder House with the Designed Heat Slab Broader a. Approximate center of the broader house 6h.8h b. 0n the broader house floor under the litter 59.37 c. On the broader house floor under the heat slab 72.18 d. Under the hover and six in. above the heat'slab 90.79 s. Under the hover and 2h in. above the heatISIab 9h.33 Between the Broader Houses, Measuring the outside Air Temperature 55.h6 31 Kilawatt hour meters were used to measure the total amount of electric energy used for brooding, including that required by the attached night lamp. Chicken mortality was recorded daily; The exact amount of feed consumed was recorded. Table 6 shows the mean tenperatures at the various locations for the entire six week brooding period. - The 12 hour mean temperatures, six a.m. to six p.m. and six p.m. to six.a.m. intervals, for the various brooders are shown in Figs. 1b, 15 and 16. Two other sets of temperature measurements for a 112 hour period, hourly temperature recordings six p.m. April 23 to one p.m. April 25, 1957, are shown in Figs. 17, 18 and 19 and.from.four a.m. May 9 to ten p.m. May 10, 1957 in Figs. 20, 21 and 22. Table 7 is an analysis of the total amount of’electric energy used for the six week brooding period. Table 8 is an account of chicken mortality, and Table 9 is an account of the feed conversion rates. TABLE 7. KILOWATT HOURS USED FOR BROODING FOR THREE BROODEBS, THE SECOND BROODING TEST w TOTAL m1 WCHICKEN M Infrared Broader Lamps Under a Wood Hover 1:56 1.815 0.166 commercial Heat slab 157 0.636 0.157 maigled Heat Slab 237 1.110 0.237 lie {kWh—u? (a .quu‘l .lI‘ 120 HO lOO £0 0 70 60 TEMPE RATURE,°F 4O 30 WM ~ \AA 1 NW w A T «A M \A A, 1 NWV A ilk/V / \ ” V T / VT ' W! U T 4/23 4/29 5/6 5/l3 5/20 5/27 TIME A.6lN.ABOVE LITTER UNDER HOVER B.REQUIRED BROODING TEMPERATURE C.ROOM D.OUTSIDE FIG.|4. TEMPERATURE VARIATIONS, INFRARED LAMP HOVER BROODER.MEAN TEMPERATURES FOR l2 HOUR PERIODS,4/23/57- 5/27/57 TEMPERATURE, °F I20 -— -_. [ _-...__ ____. IIO IOO MA ..___ I 90 wk AW A l \ \ ¢ TX 80 C 70 ‘M NA . WW ‘ 50m 7 W 40 30 4/23 4/29 5/6 5/I3 5/20 5/27 TIME A.6 IN. ABOVE HEAT SLAB, UNDER HOVER B.REOUIRED BROODING TEMPERATURE C. ROOM D. OUTSIDE FIG. I5. TEMPERATURE VARIATIONS, HEAT SLAB BROODER, MEAN TEMPERATURES FOR l2 HOUR PERIODS, 4/23/57- 5/27/57 TEMPERATURE,°F .. are I A A .0 XV VWIA mq/ .0 M ,II U/‘TK U .0 WW I I AINVA so I, ‘ I W N’ NV 40 U I 30 II 4/23 4/29 5/6 5/I3 5/20 5/27 TIME A. I2 IN. ABOVE HEAT SLAB,UNDER HOVER B. REQUIRED BROODING TEMPERATURE C. ROOM D. OUTSIDE FIG. l6. TEMPERATURE VARIATIONS, COMMERCIAL HEAT SLAB BROODER,MEAN TEMPERATURES FOR I2 HOUR PERIODS. 4/23/57— 5/27/57 O ./ TEMPERATURE,°P I20 IIO I00 90 80 7O 60 SO AMP—FNM / If” B /\C MM ( Q /,J\ xx? \ / Wag, 6PM I2AM 6AM IZPM 6PM l2AM 6AM 12PM 4/23 4/24 4/25 TIME A.6lN.ABOVE LITTER, UNDER HOVER B.REOUIRED BROODING TEMPERATURE C.ROOM D.OUTSIDE f FIG.I7. TEMPERATURE VARIATIONS, INFRARED LAMP HOVER BROODER, 6PM (4/23/57) —- :2 PM (4/25/57) TEMPERATURE,°F I20 IIO I00 90 BO 70 60 50 x AA o\ H_ W \_ P, / “MTV 6PM 4/23 I2AM 6AM I2PM 6PM I2AM 6AM l2PM 4/24 4/25 TIME A.6lN.ABOVE HEAT SLAB, UNDER HOVER B. REQUIRED BROODING TEMPERATURE C. ROOM D. OUTSIDE FIGJB. TEMPERATURE VARIATIONS, HEAT SLAB BROODER,6PM(4/23/57)— I2 PM(4/25/57I *J I20 IIO I00 3: B LU I: 90 79/ V \ r H ,3 A ’\_/— ' \/‘\N/" 5 ea - Q 5 V / +- 70 -\ \ Rhc/ VWUV/ 6O '50 6PM I2AM 6AM I2PM 6PM I2AM 6AM I2PM 4/23 4/24 4/25 TIME A. I2 IN. ABOVE HEAT SLAB, UNDER HOVER B. REQUIRED BROODING TEMPERATURE C. ROOM D. OUTSIDE FIG. I9. TEMPERATURE VARIATIONS,COMMERCIAL HEAT SLAB BROODER, 6PMI4/23/57I— :2 PM (4/25/57) TEMPERATURE,°F I20 .2: “/“W M .0 B _____, a .0 f2 A AA \ J \/ 60 \ I—\-\ \ so 40 I I 4AM IOAM 4PM IOPM 4AM IOAM 4PM IOPM 5/9 5/IO TIME A.6IN. ABOVE LITTER, UNDER HOVER 'B.REQUIRED BROODING TEMPERATURE C. ROOM 0. OUTSIDE FIG.20. TEMPERATURE VARIATIONS. INFRARED LAMP HOVER BROODER, 4AM(5/9/57)— lOPM(5/IO/57I I20 I—‘R IIO » fl I00 90 3- MN “I B N\—\QIE /\/ (I 80 ——.. E q C 5 70 \ UJ '— 60 D ‘ 5" v s “‘ 4O 4AM IOAM 4PM IOPM 4AM IOAM 4PM IOPM 5/9 5/IO TIME A.6IN. ABOVE HEAT SLAB, UNDER HOVER B. REQUIRED BROODER TEMPERATURE C. ROOM D.OUTSIDE FIG.2I. TEMPERATURE VARIATIONS, HEAT SLAB BROOOE R, 4AM(5/9/5 7) — IO PMIS/IO/S?) I20 IIO TEMPE RATURE,°F 7O 60 I [A 50 0 - 4AM IOAM 4PM IOPM 4AM IOAM 4PM IOPM 5/9 5/IO TIME A. I2 IN. ABOVE HEAT SLAB, UNDER HOVER B. REQUIRED BROODING TEMPERATURE C. ROOM D. OUTSIDE FIG.22. TEMPERATURE VARIATIONS, COMMERCIAL HEAT SLAB BROODER, 4AM(5/9/57)— IOPM(5/IO/57I Tm 8. cmcxm MORTALITY WITH THREE BROODERS, Tm SECOND BPDODING TEST Broom CHICKENS STAIfl'ED M % MORTALITT Infrared Broader Lamps Under: a wood Hover 25h 3 _ 1.182 Commercial Heat Slab 251 h 1.5911 Desigred Heat Slab 2&8 2 0.807 TABLE 9. FEED CONVETBION BATES WITH THREE BIDODETIS, THE SECOND BROODING TEST BROODER LB FEED LB GAIN LB FEED/LB GAIN Infrared Broader Lamps Under a wood Hover 735 222.1 3.309 Cannercial Heat Slab ‘ 700 233.5 2.998 Designed Heat slab 765 222.6 3.107 Individual weights of all the chickens were recorded. Tests were applied to this data to find if a statistical difference occurred between the infrared lamp broader, the commercial heat slab broader and the designed heat Slab broader, see Table 10. TABLE 10. MALE AND FEMALE CHICKEN MEAN WEIGHTS AND THE STANDARD DEVIATION OF THESE MEAN WEIGHTS FOR THE CHICKENS RAISED UNDER THREE BROODERS, THE SECOND BROODING TEST BRIDDER MALES FEMALES MEAN WEIGHT STANDARD MEAN WEIGHT STANDARD LB DEVIATION LB IEVIAIION. LB LB Infrared Broader lamps Under a Wood Hover 0.9071 1 0.208 0.81.90 1 0.191 Conercial Heat Slab 1.026).; 30.153 0.8803 2 0.1M; Heat slab Broader 0.9589 $0.129 0.8633 10.130 h2 A statistical significant difference occurred between male clickans raised an or under the following brooders: Commercial heat slab and designed heat slab Cmnercial heat slab and infrared lamp broader Designed hast slab and infrared lamp broader Results of the Third Trial Brooding Test * (See note, p. h3) A five week brooding test was conducted December 6, 1957 through January 10, 1958. Two types of brooders were used, the conventional infrared lamp broader and the designed heat slab with the hover pre- viously used in the first and second brooding tests. twenty chickens, 60 males and 60 females, were placed under each broader. Temperatures and electric energy were not meaSured because of the few chickens being used. one hundred and The brooders were designed for a larger umber of chickens and the results with fewer chickens would be mis- leading. The temperatures were checked periodically but not recorded. 011 may nights the outside temperature drapped to 0°17“ or below. Vantress Cornish ' males were crossed with Arbor Acres White Rock fe- males for the third test. female chickens. The female chickens were kept separate from the male Wing bands were used to identify male and chickens under each broader to check feed conversion rates. Chicken mortality was recorded. female chickens under the infrared lamp broader and the heat slab broader. Table 11 shows chicken mortality for male and TABLE 11. CHICKEN MORTALITY WITH INFRARED LAMP BROODER AND THE DESIGNED HEAT SLAB, FOR THE THIRD BEDDING TEST BmODER Infrared Lamp Broader Males Fanales Designed Heat Slab Males Males CH ICKENS STARTED DMD 8‘8 88‘ 0 2 Z MORTALITY I b3 The information on feed conversion rates could not be obtained because the males and females on the heat slab became mixed. The chickens Jumped overithe three foot partition which separated the two sexes during the fifth week; this was not known until a couple of days before the weighing. Table 12 shows the feed conversion rates for males and females under the infrared lamp broader and the total feed conversion ratio for the heat slab brooder. TABLE 12. FEED COMIRSION RATES WITH INFRARED LAMP BROCER AND THE DESIGNED HEAT SLAB BROODER, FOR THE THIRD BROODING TEST J BmODING METHOD LB FEED LB GAIN LB FEED/LB GAIN Infrared Lamp Brooder Males 162 8109 10977 Females 152 71.9 2.118 combined sexes 311; 153.8 2.0143 Heat Slab Brooder | Combined Sexes 285 1147.1; 1.932 Individual weights of all the chickens were recorded. With this data statistical tests were applied to find if a statistical differences occurred between the infrared lamp broader and the heat slab broader. Table 13 shows the mean weights and the standard deviations of those mean weights for the male and female chickens.' The test showed no «- statistical significant difference between males and fmales. at t Test was used to find the statistical significant difference, the results are based on 92 per cent confidence limits. TABLE 13. ML MEAN WEIGHTS AND STAI-FDARD DEVIATIONS OF THESE MEAN WEIGHTS FOR MALE AND FEI-IALE (HICKENS UNDER DIFRAIED LAMP BmODBR AND THE DESIGNED HEAT SLAB, mm) BROODING TEST BROODING METHOD MAI ES MEAN WEIGHT DEVIA‘I’ION Infrared Lamp BrOOder 1.36; lb. 100156 1b. Heat slab Brooder 1.352 lb. 110.173 1b. FEIVLAIBS MEAN W EIGHT DEVIATI ON Imus 1b. 1.185 lb. £0,167 lb. 1.215 1b. DISCUSSION OF RESULTS A definite procedure should be established for designing radiant type brooders for chickens. Data has been collected over the past 25 . years on radiant chicken brooding, but a definite procedure for design- ing a radiant breeder for chickens is not available. Utilizing the information in the "Review of Literature," a suggested procedure was established. DESIGN PROCEDURE FOR A RADIANT CHICKEN BROODER A. 1. Establish the number of chickens per brooder, if the output of the breeder is known, i.e. as with infrared brooder lamps, and it is desired to know the brooding capacity see part B. 2. Find the projected area of the chicken; if the age of the chicken is known use the chicken's age; if it is not known, design for a four or five day old chicken, Fig.12. 3. Knowing the average coldest room temperature and the age of the chicken find the amount of heat required for Proper growth. Fig- 3. h. Multiply the heat required, Btu/inz/hr, by the projected area of the chicken, in2 of chicken; the product is the heat required per chicken per hour. 16 be 5. step four gives the heat required per chicken, find the heat required for all the chickens. For design wattage, one watt hour is equal to 3.h13 Btu. B. 1. Find the Btu output per hour of the broader, one watt hour is equal to 3.h13 Btu per hour. 2. Follow steps two, three and four as in part A. 3. The brooding capacity of the broader must satisfy two conditions; a. The heat requirements for each chicken; Btu (output)/in2/hr . Btu (required by chicken)/in2/hr. b. The sum of the projected chicken areas should be at least 25 per cent less than the radiated floor surface area of the broader. The heat slab type broader was designed following the above pro- cedure. It was first conceived that the heat slab broader might be used by itself without the aid of a hover type heat trap. with this typothesis, radiation patterns were determined with the heat slab. Mercury thermometers were first used to establish a heat pattern above the heat slab. The temperatures six inches above the heat slab were two to eleven degrees F above room tenperature. The heat slab surface temperature was not high enough to fulfill the brooding require— ments set forth by Seeger and oliver, Fig. 3. An Eppley radiation meter was used to find the total infrared radiation output from the heat slab and from infrared broader lamps. h? The radiation output of the lamps could be compared with the pub- lished data of Fig. 1. This would have been an ideal criteria for comparisons. The meter had a filter that filtered out a great portion of the infrared spectrum. The filter could not be removed, so the readings were invalid. It was established that the heat slab broader was not a true radiant heat source, but a heat source for conduction and convection heat transfer. A chicken could lie down an the heat slab and receive energy by conduction; when the chicken would walk on the heat alab energy was transmitted to the chicken by convection and very little by radiation. The stefan - Boltzmann Law for black body radiation pro- vides the basis for the last statement. The radiant heat output, Btu per hour, of the heat slab; q = Aep(Tl; - Ti), Stefan - Boltzmann Law A : l6 rte, area of heat source, the heat slab broader 5 g 0.90, assumed emissivity for masonite 9-.- O.l73 X 10-8 Btu/hr ft2 oRh(Rankine degree), a constant T1 u (80 h60)°R, slab surface temperature without a hover T2 = (30 h60)°R. room temperature . q a 16 x 0.90 x 0.90 x 0.173 x 10"8 x((5h0)l‘-(h90)l‘) q z 155 Btu/hr, radiant heat output of the heat slab seven hundred and eighty watts of electrical mergy were being used per hour which is equivalent to 2662 Btu per hour. The remaining heat; 118 2662 Btu/hr - 155 Btu/hr = 2507 Btu/hr was being transferred by convection to the air and by conduction through the insulation of the heat slab. With this type of heat source a heat trap will have to be used. The problem was to desigr a heat trqw that would retain the advantages of infrared broader lamps and minimize the loss of heat due to power interruptions. One of the advantages of the infrared broader lamps was that the chickens could be seen at all times. With this important considera- tion foremost, a clear plastic sheet hover was designed. The plastic used reflected the long infrared waves and transmitted the short infrared wave lengths. It would be desirable to have a plastic that reflected both long and short infrared wave lengths. The plastics investigated would do one or the other and not both. The plastic hover maintained desirable brooding temperatures. When an aluminum top was installed on the plastic hover electrical energy consumption was reduced. Fig. 6 shows the final hover. A wood hover maintained desirable brooding temperatures, but this advantage was disregarded in favor of the clear plastic hover with an aluminum top because of the visibility through the clear plastic. The heat balance of the plastic sheet hover with an aluminum top is as follows, assuming the available heat above the heat slab is transmitted by convection; radiant heat is present but in very small amounts . Heat output, Btu per hour, of the heat slab broader; q :- “(t1 - t2), heat transfer for convection heating h : surface conductance and it. is dependent on temperature and the position of the surface .A : surface area of the heat source t1 = surface temperature of the heat source t2 -_- air temperature surrounding the heat source The following calculations are necessary to solve for the heat required to maintain an air temperature of 82°F under the hover; The surface conductance for a flat surface over one square foot and heating upward: h = 0.38(At)% At : 122-82, heat slab surface temperature minus the air temperature under the hover at g [10°F h : 0.38 (110)“:i h z 0.98 Btu/n2 hr OF and, q = “(t1 - '52) q : 0.98x 16 1 (122-82) A : 16 rte surface area of heat slab t1 3 12201" heat slab surface temperature t2 : 82°F air temperature under hover q : 62h Btu/hr. heat loss from the heat slab to the air under the hover 50 The heat loss from inside the hover to the air in the broader house is assumed to be lost by convection. The hover top and sides are approximately the same temperature as the air under the hover, the plastic conducts heat very rapidly and the aluminum by itself conducts heat rapidly. The aluminum receives its insulation value from the air film layers on each side of the sheet; however there are forty feet of crackage on the top of the hover from which heat escapes, therefore the film layers of air can be neglected and the alumirmm is assumed to be the same temperature as the air under the hover. The hover is assumed to be a rectangle having dimensions of 2.5 x 21.0 square feet on each side and 14.0 1 1.1.0 square feet on the tap and bottom. The surface conductance for a vertical surface more than one square foot and more than one inch wide is: h a 0.12(ht)* At = 82-30, air temperature under the hover minus the roan air; temperature 11 a 0.12(52)% h 3 0.325 Btu/rt2 hr °F and, q a ham - 1:2) A s 2.5 x tho 1 21.0 a 1.0 ft2 vertical hover surface area t1 - t2 3 82-30, air temperature under the hover minus the room air temperature (1 = 0.325 I to x (82-30) (1 g 675 Btu/hr. heat loss through the vertical sides of the hover 51 The surface conductance for a flat surface more than one square foot and heating upward: h = 0.38 (Atfi 4t : 82-30, air temperature under the hover minus the room air temperature I: = 0.38 r (52)i h = 1.025 Btu/rt2 hr °p and, C1 = hA(t1 - t2) A : 16 ftz, the surface area of the top of the hover t1 - t2 = 82-30, air temperature under the hover minus the roan air temperature q = 1.025 x 16 x (82-30) q : 852 Bin/hr. heat loss through the top of the hover. The total heat transfer through the heat slab top surface is equal to the heat required to warm the air under the hover plus the heat loss of the vertical sides andthe top of the hover. q 2: 62h 1- 675 + 852 q = 2151 Btu/hr. heat loss through the top of the heat slab The average electric consumption was 0.75 kwh for the above con- ditions, therefore. 0.750 kwh x 31113 Btu/kwh hr .1..- 2560 Btu/hr output of the heat slab and, 2560 - 2151 = 1:09 Btu/hr heat loss by conduction through the bottom and sides of the heat slab. ‘- 52 The convection theory of teat transfer accounts for most of the heat; it also accounts for a reasonable loss through the bottom insu- lation and through the wood frame sides of the heat slab. Figure 13 shows how the temperature decreases under the empty hover when the circuits are de-energized. With chickens under the hover the temperature under the hover would remain hi gher for a longer period. The heat slab hover broader definitely minimizes the power interruption disadvantage of infrared broader lamps. Two hours after the power interruption the temperature was 65°F six inches above the heat slab surface, under the hover, with a roan temperature of 20°F. This would not be harmful to chickens. U.S.D.A. reported that chickens can be chilled at 37°F for one and one half hours without impairing their growth rate. A two hour power intermptian‘would be fatal to the major ity of chickens under an infrared lamp broader in a room of 20°F. The results of the first trial brooding test were to be used as indications of the brooding effectiveness of the two brooders used. The indications were: reduced mortality; increased feed conversion rates; and'lower electric energy consumption with the advantage in favor of the heat slab broader. The chickens behaved very well an the heat slab. one interesting - observation during this test and the next two was that a cold chicken would lie down on the heated surface and fan out its wings to increase the body surface area so it could absorb more heat by conduction. The results of the second trial brooding test were treated more critically than the first brooding test. A detailed study was made 53 from the recorded hourly temperatures under the hovers of the brooders. The heat slab broader was used without any corrections or additions. The thermostat settings for the heat slab broader were made according to the graph on taupemture requirements versus chickens age, Fig. 11. A wood hover was used for the infrared broader lamps to try to reduce the electric energy consumptimr. A canmercial heat slab broader was used for brooding and it was compared with the infrared lamp broader and the designed heat slab broader. An analysis of Fig. 111 through 22, the hourly temperature record- ings under the hovers, provided a criteria for measuring the relative effectiveness of the hover type brooders. l. The infrared broader lamps with the wood hover; b. Temperatures under the rover were consistently higher than required for proper chicken brooding. The temperature fluctuations under the hover were similar to the outside temperature fluctuations. This is not desirable. The hover should maintain a constant tanpera- ture. The additional heat from the lamps radiation would canpensate for the difference in cold weather and would add to the chickens! discomfort on warm chys. The hover eliminated ucomfort'zonesfl that are manually established with infrared broader lamps. 2. The heat slab broader: The temperatures under the hover followed the required brooding temperatures established on Fig. )4. Variations 5h did occur when the outside tanperatures dropped to low values. The reason for this may be that the chickens remained under the hover for longer periods and this raised the temperatures under the hover. b. The hourly temperature variations indicated that the broader could maintain constant temperatures under the hover for a wide range of outside temperature variations. 3. .Comnercial heat slab broader; a. The temperatures were erratic under the hover, following a temperature curve similar to the infrared broader lamps. The thermostatic control was not calibrated and as a result was difficult to set for proper temperature control. b. The hourly temperatures under the hover indicated that the broader held a constant under the hover temperature. Temperatures varied more with the heat slab broader than with the infrared lamp broader. The caninercial heat slab broader consumed the least amount of electric emery, 0.636 kwh per chicken, as compared to 1.815 kwh per chicken for the infrared lamp broader. The infrared lamp broader had the highest emery brooding cost. A thermostat could have been installed under the hover with the infrared broader lamps but it would have had to work almost constantly. The high emery output of the lamps would have activated the control and the lamps would have been de-energized and the rapid cooling of the hover would again activate the control. Ito as- - our! I . ' ‘ Shah-'ru'dtr‘vguli r- r- . ‘figzfl'h" . - . -m‘ . L ;'. e... fit. I . 55 The chickenwlartality'was less than two per cent for all'brooding methods. The highest mortality'was 1.59h per cent with the commercial heat slab broader. One possible reason for this was in the construction of the hover) the hover'was 12 inches high and ventilation was a problem. The heat slab surface was 12 square feet and the larger chickens could easily suffocate small chickens under the hover by crowding. The feed conversion rates were poor, varying from 3.1437 to 2.998 pounds feed per pound gain. The highest feed conversion rates were with the heat slab broader and the lowest feed conversion rates were with the commercial heat slab broader. The reason for'the high feed conversion rates was probably due to a mixed breed of chickens, some of which were not too efficient in converting feed to meat. One interesting result is reported in Table 10, the mean weights and the standard deviations of these mean weights for male and female chickens. The cmmercial heat slab broader had the highest mean weights and the designed heat slab broader had the lowest standard deviations which indicated a greater consistency in the weight of the chickens. The infrared lamp broader had the highest standard deviations and lowest mean weights indicating wide variations in the weight distributions. 6 statistical significant differences in weights occurred between males in all the brooders but not between females. This would indicate that there may be a preference in the type of broader for the brooding of male chickens for meat. These results led to the third.broading trial to test this difference. 56 The third brooding trial utilized a Vantress Cornish x Across White Rock breed of chickens. The mortality was low, with the indi- cation that mortality is higher for females. I Accurate feed conversion rates were obtained for the chickens under the infrared lamp broader. The males were slightly more efficient than faceles. The partition for the heat slab broader was not chicken proof; male and female chickens mixed curing the week before weighing. The combined feed conversion rates for both sexes were obtained. The combined feed conversion rate was higher for the infrared lamp broader, 2.01:3 to 1.932 pounds feed per pound gain. The mean weights of the male and female chickens raised under the infrared lamp broader were higher and the standard deviation of the mean weights was less than for the chickens raised in the heat slab broader. This was a complete reversal of the second brooding test. There‘was no statistical difference between the male and female chickens. The heat slab broader used less electric energyr for brooding and chicken mortality was lower with heat slab brooding. SUMMARY Indiant type chicken brooding is very popular among chicken powers. In many cases the term radiant heat transfer is misleading. Radiation heat transfer requires no conducting or convection medium. Infrared broader lamps are truly radiant type heaters. Many of the radiant type brooders are not truly radiant. A very small portion of the total heat is enitted in the farm of infrared radiation. The majarity of the heat transfer is by conduction or convection. The heat slab broader constructed in this experiment was designed as a radiant heater; it turned out to be a heat source for conduction and convection heat transfer. - A heat slab broader was designed for Michigan conditions. The broader worked satisfactorily during three brooding seasons: mid- winter; early-spring; and late-spring. The initial cost of the heat slab broader was higher than for a corresponding infrared lamp broader. The life of the broader was undetermined. It was assumed that it will last as long as the materials of which it is made will last. The maintenance of the broader hover would be a few cents per year; the plastic sides on the hover would have to be replaced. The heat slab broader and a plastic hover with the aluminum top offers many comparable advantages of the infrared broader lamps; the chickens can be seen at all times; and it is easily installed and operated. 57 58 The heat slab minimises two of the disadvantages of infrared lamp brooders; a complete loss of heat due to a power interruption; and high electric brooding costs. The heat slab broader will retain a temperature of 65°F for at least two hours and temperatures above 37°F for a longer period of time after electric circuits are de-energized. The heat slab broader should be energized 214 to 36 hours before chickens are placed in it. There was no difference in feathering or growth rates of the chickens under the various types of brooders. Chicken behavior was similar under the infrared lamp broader and the heat slab broader. Chicken mortality was less with the heat slab broader than with the infrared lamp broader. Under the infrared lamp broader the stronger chickens would retain positions in the various "comfort zones" averting the weaker chickens fran these zones. Chickens on the heat slab broader can receive the benefits of proper temperature and there is enough room for all the chickens. when infrared broader lamps were used in conjunction with a hover, desirable brooding temperatures were very difficult to maintain. Temperature fluctuations under the infrared lamp broader were similar to outside temperature fluctuations. The heat slab broader tempera- tures usually increased with outside temperature drops. This was probably due to the chickens remaining under the hover for greater periods of time and thus providing an additional heat source, the chicken's body. 59 The commercial heat slab broader was used during the late-spring brooding period. The results of one late-spring test are: reduced electric energ consumption and increased chicken mortality. In view of thediscussed considerations, a heat slab broader of most practical capacity limits, can be designed for Michigan conditions. A heat slab broader designed for radiation heating will supply ample heat for convection heating if the heat slab is insulated and a hover trap is used. The required brooding tempera- tures, Fig. 1;, should be followed for minimum energy requirements. EFEIENCES Baker, V. H. and Waters, J. H. (1951) Brooding Poultry with Infrared Energy, Agricultural Engineering Journal, vol. 36, no. 6, pp. 316—326: June. Barr, N. T. and Hough, J. 3., Electric Underfloor Brooding, American Society of Agricultural Engineers, st. Joseph, Michigan. Brown, D. P. (1952) Prevention of Frost Damage in orchards by Using Hind Machines to Utilize Temperature Inversion with and without Petroleum Burners, Thesis, michigan state College. Bryan, John (1955) Electric Slab Brooding, Farm Electrification, vol.' Ix, no. 1, Edison Electric Institute, pp. lU-lI, January—February. 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(l9h8) Radiation Uses and Needs in Agriculture, Agricultural Engineering Journal, pp. 1115-1246, April. Radiant Energy Brooding in Units of 500 chicks, Farm Industry Division, revised, March 12, 1951. Radiant Energy Supplementing Floor Heat Broads Chicks for the small Poultryman, Farm Industry Division, revised, March 7, 1951.. Rhodes, A. J. (1956) Portable Underheat Brooding, Farm Electrification, Vol. V, No. 5, pp. 10-11, Edison Electric Institut'S, septErEer-ocfiber. 62 Seeger, K. C. and oliver, J. H. (1951) Radiant Energy Chick Brooding, Agricultural Engineering Journal, vol. 32, no. 5, pp. 278-280, May. side Curtains cut costs, Farm Power, pg. 11;, January, 1957. Underfloor Brooding Appeals to Poultryman, Electricity on the Farm, pp. 10-11, February, 1957. Uses Plastic for Broader, Successful Farming, pg. 151, April, 1957. Whithead, M. 0. (1951) Underfloor Heat Broader, Agricultural Engineering Journal, pp. 608-611, November. .‘i- 7., .91 _ u l » .,.'.” ”.3 .. . ‘ W 1:.)- Rui us: cm GAN ”'liwmjumyi’flifliflifiwflflfijfi1W“