Study On Flow And Pressure Pulsation Characteristics Of Swash Plate Connecting Rod Axial Piston Pump

As one of the core components of the hydraulic system,the axial piston pump has the advantages of high pressure,high efficiency and low leakage,and is more and more used in the ship bilge drainage system.Compared with the common slipper swash plate type piston pump,the motion form of the transmission mechanism of swash plate connecting rod type piston pump is more complex,but the motion of the piston is more simple.The two are different in the flow and pressure pulsation characteristics.In this paper,the swash plate connecting rod type axial piston pump is taken as the research object.Based on the existing research theories and methods of pulsation characteristics,the pulsation frequency of the piston pump is analyzed from the perspective of the piston motion characteristics,and the quantitative relationship between the flow pulsation rate and the pressure pulsation rate at the pump outlet is further studied.The main research contents of this paper are as follows:(1)The kinematics analysis of the main moving components of the swash plate connecting rod type axial piston pump was carried out,and the formulas for the displacement,velocity and acceleration of the piston were derived with time,and the derivation results were plotted using MATLAB software.On the basis of kinematics analysis,the formulae for calculating flow pulsation rate and pressure pulsation rate of pump output are derived,and it is found that the pressure pulsation rate is 2 times of flow pulsation rate under the same condition.(2)ADAMS software was used to complete the kinematics simulation of the piston,and the simulation results were imported into AMESim software to establish the simulation model of the hydraulic system of the piston pump,and then the simulation of the flow and pressure pulsation characteristics under different speeds and load conditions was completed.It is found that the flow and pressure pulsation frequency at the piston pump outlet is 5Hz at the rated speed.The main reason is that the axial swing speed of the swash plate is not uniform,and the motion characteristics of each piston connected with the swash plate are not completely the same,which leads to the spindle rotating once and the piston motion changing periodically twice.Under the same simulation condition,the output pressure pulsation rate of the pump is about 2 times of the flow pulsation rate.(3)According to the hydraulic simulation system and the existing test equipment,the test platform was built to test the pump output pressure,and the theoretical derivation and simulation results were compared and analyzed.The results show that the measured pressure pulsation rate is low,which is mainly related to the pump structure and the test environment conditions.The pump outlet pressure pulsation frequency is 5Hz,which is consistent with the simulation results.The test proves the accuracy of the simulation and theoretical analysis.