Abstract：Aiming at the friction and lubrication failure problem of the oil film on slipper pair in high-pressure and large-displacement radial piston pump, the numerical simulation of fluid-structure-thermal coupling was carried out for the flow field and solid domain structure of slipper pair under the consideration of the weak compressibility, viscosity-temperature and viscosity-pressure characteristics of oil. The influence of working conditions on the oil film bearing characteristics of the slipper pair and the variation of the structural strength of the slipper and the stator were discussed. The results show that with the increase of the working pressure of the piston pump, the oil film pressure of the slipper pair increases greatly, and the velocity field and temperature field of the oil film remain basically unchanged. With the increase of the piston pump rotation speed, the oil velocity and temperature of the slipper pair oil film increased greatly, and the pressure field of the oil film is basically remained unchanged. The maximum deformation and stress of the slipper appeared at the outlet edge of the damping hole at the bottom of the central oil cavity. The geometrical structure of this part is thin, and it has to bear the high pressure oil pressure load and temperature load of the central oil cavity, so it is the weakest part of the whole slipper structure. At the same time, the oil film temperature rise caused by the heat generation of viscous friction has a great influence on the structural strength of the slipper pair, which is also an important factor limiting the rotation speed increase of the piston pump. The results can provide some reference for the optimization design of high-pressure and large-displacement radial piston pump slipper pair.
