| Swash plate type axial piston pump is a very important power component for modernhydraulic systems, which is widely used in aviation, aerospace, petrochemical,construction machinery and many other fields. Piston/Cylinder Interface andSlipper/Swash Plate Interface are two key friction interfaces in axial piston pump, theyare the fundamental guarantees for piston pump to achieve its function. With theimprovement of working pressure and speed in piston pump, the lubricationcharacteristics of Piston/Cylinder interface and Slipper/Swash Plate interface haveimportant impact on pump’s performance and life. The study of dynamic characteristicsof lubricating needs to fully consider the coupling between machine and fluid thatfriction within. A dynamical decoupling scheme is present in this thesis, throughembedding lubrication model into the dynamic calculations in a multi-domainco-simulation way. Dynamic lubrication characteristics analysis of Piston/CylinderInterface and Slipper/Swash Plate Interface will provide guidance for performanceoptimization and life analysis of core parts in piston pumps.Pressure control equations have been modeled according to flow state of the oil filmin Piston/Cylinder interface and Slipper/Swash Plate interface, which considered thediffusion, squeeze film effect and hydrodynamics. Through the analysis of Reynoldsequation based on the finite difference method, the oil film pressure, leakage flow andfriction force of the friction pair were obtained. For the convenience of communicationwith multi-body dynamics calculations, the film forces were converted into a generalforce in an equivalent way, thus a relationship between the space posture of piston andslipper with their film force has been built.In order to meet the requirements of analysis platform, a swash plate type axial pistonpump parametric modeling system has been established in dimension-driven mannerusing Pro/E for a secondary development. The system export graphic files and massparameters needed for dynamic simulation. Through analysis of the state of movementof piston and slipper, forces acting on the piston and slipper were modeled. And thedynamic simulation model of an axial piston pump is built in this paper by use of Clanguage subroutines based on Piston/Cylinder Interface and Slipper/Swash PlateInterface lubrication model.Finally, based on dynamic simulation model of the piston pump, the dynamiclubrication characteristics of Piston/Cylinder interface and Slipper/Swash Plate interfacewere analyzed. This paper mainly focus on the film thickness, pressure, friction andleakage trends and causes in those friction pairs. By setting various simulation conditions, key performance indicators were analyzed with the change of load pressure,swash plate angle and spindle speed. |
PDF Full Text Request