Numerical Simulation And Visualization Research On Transient Flow Field Of Port Plate Pair In Plunger Pump

The hydraulic system vibration is one of the key factors that effects reliability of the hydraulic system and hydraulic pump is the main vibration source of hydraulic system. The pressure pulsation and flow fluctuation induced by the most widely used axial plunger pump is the main factor of causing piping vibration in hydraulic system and fluid noise. The irregular vibration of the flow field caused by unsteadily existing of vortex is one of the pulse excitation source in the axial plunger pump. As the analyzing of flow structure and flow mechanism is an effective mean to study the cause of flow pulsation and the generating mechanisms of noise in axial plunger pump, so it is of great importance to noise reducing and noise control of plunger pump.Using the method of numerical simulation combined with experiment, the thesis studied the following aspects of content based on the axial plunger pump as the research object.The first chapter analysis the structure characteristics of axial plunger pump and motion law of plunger. The model of numerical simulation and PIV experiment is calculated according to the similarity theory. At last the mode test and operating conditions of single plunger- valve plate is got.The second chapter focuses on numerical simulation analysis of process of matching flow. Three-dimensional flow field model of single plunger-flow plate is established. The formula for flow area of flow distribution process is summarized. Combined with the experiment data, the inlet velocity curve is fitted and loaded into the fluid simulation with the UDF program. The flow field distribution with different inlet velocity and plunger movement speed is dynamically simulated. The effect rules of vortex structure、size、strength and local pressure loss are obtained.The transient flow field of process of matching flow is tested with PIV in three chapter. The slide block model of single plunger- flow plate is designed. The PIV test-bed which is used to test the flow dynamic characteristics of single plunger-flow plate is set up. The experiment of transient flow field is made with different inlet velocity and plunger movement speed. The test result provides experimental basis for the math model and the flow field simulation.The last chapter analyzes characteristic of flow field in the whole axial plunger pump. The three-dimensional flow field model of whole pump is established. The complex movement of plunger which drives back and forth as same as rotates is realizable with dynamic mesh model. Taking into account of oil compressibility, the law of oil flowing backward, the flow pulsation and the pressure fluctuation is obtained at different load pressure and pump speed.