Design And Performance Analysis Of Compound Vacuum Pump Based On Straight Claw Double Claw Rotor

In order to improve the working performance and reliability of dry vacuum pumps,the commonly used meshing curve method and the commonly used curve meshing model of claw rotors are summarized,and the profile characteristics of the existing curved claw rotors and straight claw rotors are compared.A new type of double-claw rotor with straight claws without sharp points is proposed.The shape parameters of the straight-claw double-claw rotor are studied,the rotor profile structure is designed,and the parameter equation that composes the profile curve is obtained.The influence of the shape parameters on the performance of the claw pump is: the claw length coefficient increases,the volume ratio between the claws and the suction volume ratio increase,and the compression volume ratio decreases;the center angle of the claw top arc increases,the volume ratio between the claws,the suction volume ratio and The compression volume ratio decreases.The performance of the proposed straight claw double claw rotor is better than the ordinary straight claw single claw rotor.The application of the straight claw double claw rotor improves the suction efficiency of the vacuum pump and enhances the operation stability of the claw pump.Using simulation analysis,the internal flow field of the straight-claw double-claw rotor vacuum pump and the gas flow changes in the inlet and outlet ports are studied.Based on the straight claw double claw rotor,a multi-stage dry compound vacuum pump with a combination of roots and straight claw double rotor is designed.Completed the structural design of the composite vacuum pump.The composite pump has a larger pumping rate under low pressure conditions,and has the advantages of both a Roots pump and a straight claw double claw vacuum pump.It has a higher pumping speed and higher than ordinary claw pumps.Lower energy consumption,and the same higher ultimate vacuum as the claw vacuum pump,while having a larger pumping speed,while reducing the volume of the pump.Finally,based on the basic theory of fluid numerical simulation,the modal equation of the flow field inside the pump cavity was selected,and the best turbulence calculation model was selected for the simulation analysis;a multi-stage straight claw double claw vacuum pump and a compound vacuum pump flow were established Field simulation model,using CFX to solve the results,analysis and comparison of the internal pressure field and suction and exhaust port flow changes of the two pumps,clarified the performance advantages of the compound vacuum pump compared to the multi-stage straight claw double claw vacuum pump.