In order to compress water vapor as refrigerant, most modern impeller confronts a lot of challenges since the impeller has to be made with strict material and structure requirements. This thesis investigates a novel composite axial impeller to achieve the compression goal which is also able to solve those challenges. Based on an advanced concept, this thesis realizes automatic manufacturing composite impeller as well as its mechanical properties characterization, rotor dynamic and aerodynamic related impeller performance analysis. Refrigeration cycle process is modified to compress water vapor as refrigerant and coefficient of performance is able to increase for about 30%. The modified cycle comes up with requirements to rotating impellers such as rotating speed, pressure ratio and efficiency. In order to produce impeller with satisfied mechanical properties, a CNC machine based novel platform is developed to manufacture composite impeller automatically; its mechanical properties are experimentally tested and results show that this approach is able to manufacture the quality of composite impeller as desired. A new methodology is developed to predict composite rotating impeller's fatigue life, especially for ones with complicated geometries when aerodynamic force is not negligible. Pattern's effects from aerodynamic views are compared and flow structure inside of blade angle optimized impeller channel shows that a serious boundary layer separation exists between 30% and 50% impeller span zone. The investigation brings a concept up to the table and develops a novel axial composite impeller for compressing water vapor as refrigeration. Using this axial impeller, blade angle and geometries have been optimized to prevent boundary layer separation and through investigation, it demonstrates specific pressure ratio and efficiency can be achieved to reach the goal of compressing water vapor as refrigerant.
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