Dynamic response analysis of composite clearance fault in reciprocating compressor transmission mechanism

The traditional Hertz contact model has the problem of mismatch in the scope of application when analyzing reciprocating compressor clearance faults. Therefore, a modified conformal contact force model is proposed in this paper, based on the L–N contact force model, and the modified stiffness coefficient Kc and the modified stiffness index nc are introduced to obtain the modified conformal contact force model. The validity of the modified conformal contact force model was verified by developing simulation model and theory dynamics equations. Based on the simulation model, the effects of different clearance values, different clearance fault locations, and different operating conditions on the dynamic response were investigated. The accuracy of the simulation model was verified by performing fault tests on reciprocating compressors. The simulation results show that, as the number of bearing clearance faults increases, the acceleration of crosshead vibration decreases, and the addition of slide clearance faults increases the acceleration of crosshead vibration; as the friction force and rotational speed increase, the amplitude and frequency of cross head vibration impact under composite clearance faults will be further intensified. For the study of clearance faults in the same type of mechanism, the work done in this paper can be a reference.