The Research Of Rotor Profile And Thermodynamic Process For Claw Type Fluid Machinery

Claw type rotors is the key component in claw type fluid machinery,their profiles affect the claw type fluid machinery's performance directly.In order to build the perfect claw type rotor geometry profile theory for claw type fliud machinery,this paper puts forward the claw type rotor independent geometry profile parameters,including radius ratio,claw top arc angle and claw cusp arc radius which based on the research of the existing curved claw type rotor,straight claw type rotor and novel circular arc claw type rotor.The performance of claw type fluid machinery affected by the claw type rotor geometry profile parameters is analized,like relative clearance volume,capacity utilization,volume ratio,flow etc.The working characteristic and mechanical characteristic of different geometric profile parameters for claw type fliud machinery are analyzed.The flow field of claw type fliud machinery and the stress of rotors are analyzed by the numerical simulation.Due to the cusp defects of claw head,a novel circular arc straight claw type rotor is putted forward.The performance of curved claw type fluid machinery and straight claw type fluid machinery are compared,and the application conditions for two type claw rotors are obtained.The working process characteristic of claw type fluid machinery with special mixing process is studied,including thermal property and dynamic characteristic,and the changing rules of working process characteristic are found out.The cycle changing rules of the thermal process and dynamic characteristic for claw type fluid machinery with special mixing process are revealed.The research results show that: the performance is affected by the geometry profile parameters of rotors.The bigger the radius ratio,the higher the relative clearance volume,capacity utilization and flow,the lower the volume ratio,the higher the compressibility,and the worse the strength of rotors;the bigger the claw top arc angle,the relative clearance volume first decreasees and then keeps constant,the volume ratio first increasees and then keeps constant,the capacity utilization first keeps constant and then decreasees,the flow and the compressibility keep constant,and the better the strength of rotors;the bigger the claw cusp arc radius,the compressibility keeps constant and the better the strength of rotors.The novel circular arc straight claw type rotor which is putted forward has better meshing performance and higher strength.The compression ratio of curved claw type rotor is 5% higher than straight claw type rotor,so the curved claw type rotor has higher compressibility.The strength of straight claw type rotor is better than curved claw type rotor,and there is stress concentration phenomenon in the back of curved claw type rotor.The pressure and temperature in suction chamber and compression chamber are higher than the nominal suction pressure and temperature which are influenced by mixing process,and the smaller the clearance volume,the smaller the impact of the mixing process.In conclusion,this paper provides theoretical basis for the development of claw type rotor profile,and have guiding significance for the design of the claw type rotor geometry profile in the claw type fluid machinery.