Study On Characteristic Parameters Of Twin Screw Vacuum Pump

When the twin screw vacuum pump works,it is difficult to study the rotors,flow field.Compared with the experimental method,the finite element method has the characteristics of flexibility,high efficiency,direct viewing,economy and strong operability.In this paper,the dynamic performance of the rotor,the thermal deformation of the rotor and the pump cavity and the flow field in the pump cavity are studied by means of the combination of theoretical calculation and finite element analysis.The main contents are as follows:1.It is proved by theoretical calculation that QT500-7 satisfies the performance requirements of screw pump.To establish the rotor model,analyse the stress and deformation,the equivalent stress distribution and force deformation of the rotor are obtained;2.The finite element model of the rotor and the cavity is established.The temperature distribution and thermal deformation are obtained.The thermal deformation of the rotor and the cavity are compared and analyzed,and the clearance values of the assembly in four working conditions are calculated;3.Based on the similarity principle,a simplified finite element model of the flow field in the screw pump is established.Based on FLUENT,using the finite element analysis of dynamic mesh technique,the distribution of gas pump cavity pressure field,velocity field and temperature field,reveal the regularity of flow field,and can clearly capture the regurgitation and noise sources.The research content of this paper provides a simulation method and theoretical basis for the optimization design of the twin screw vacuum pump.