A Study on the Dynamics and Vibration Behavior of an Axial Piston Pump Using Combined MBD/FE Approach

In the present work a combined multibody dynamics(MBD) and finite element(FE) approach is developed for modeling the dynamics and vibration behaviour of an axial piston type hydraulic pump. A MBD model of the pumping mechanism is developed to predict the dynamic excitation forces at the bearings and control piston locations. The dynamic excitation forces in the frequency domain are obtained using fast fourier transform (FFT) with a rectangular type windowing function. A detailed FE model of the pump is developed consisting of the internal components, housing, and end cover. The dominant mode shapes and natural frequencies of the pump assembly are studied. The forced vibration behaviour of the pump is predicted by using the dynamic excitation forces from the MBD model. The numerical results are compared with the experimental results and a good agreement is found. Further, numerical studies are carried out to study the influence of component mass and stiffness on the vibration response.