System Characteristics Analysis of the Rotor in Axial Piston Pump

System characteristics of the rotor in a swashplate piston pump in hydraulic system are investigated in this paper. According to the motion laws of the piston pump, the rotor of the piston pump is discretized into limited number of elements, and the dynamic characteristics of each element is solved using the finite element method (FEM). The fluctuation of pressure and the variation of bearing stiffness is taking into consideration in establishing the FEM model. Results show that the system characteristics of the rotor is strongly affected by the pulsating pressure and bearing stiffness. Specifically, with the increase of bearing stiffness, the critical speeds of the rotor increase, where the increase of the low-order critical speeds are much more significant. Besides, the first-order critical speed also increases with the increase of pulsating pressure.