Research On Output Flow Pulsation And Dynamic Characteristics Of Axial Piston Pump

The axial piston pump has been widely used in industrial field because of its advantages of compact structure, high power density, high efficiency and easy to control variables. Due to lack of technical innovation, there are great difference between domestic axial piston pumps and foreign products in aspects of stability,responsiveness, noise and reliability. Therefore, the output flow stability and dynamic response characteristics of axial piston pump are analyzed in depth, which is of great significance to improve its working performance and engineering application value.In this paper, in order to reduce output flow pulsation and the noise in fluid distribution process of the axial piston pump, and to improve its dynamic response characteristics, the A10VNO axial piston pump is taken as the research object, its structure feature and working principle are described. The theoretical instantaneous output flow model of axial piston pump in ideal state is established, and MATLAB is applied to simulate and analyze the output flow pulsation of axial piston pumps with the odd (5, 7, 9, 11) and even (6, 8, 10, 12) pistons. On the basis of that, the output flow theoretical model of axial piston pump when considering the leakage and fluid distribution process is built, and six different port boundary conditions are set up, the simulation and analysis of the output flow rate of piston pumps with the even (8, 10,)and odd (9,11) pistons are carried out by MATLAB, and the influence of the leakage ,the pre-compression angle and misalignment angle of the port plate on the output flow pulsation of the pump are obtained.Based on the theoretical model, the whole model of axial piston pump when considering the leakage ,the fluid distribution process and fluid compressibility is established in AMESim, and the influence of swash-plate angle, the prime mover speed and the piston diameter on output flow pulsation of the piston pump are acquired by simulation analysis. And then, six different port boundary conditions corresponding to theoretical research are built to get six different port flow area curves that are imported into the sub-model of spline curve switch, and the effect of port plate structure on output flow pulsation of the axial piston pump is studied.Theoretical and simulation research results show that, in order to reduce the pressure impact and flow pulsation of the piston pump effectively, it is the most reasonable that the pre-compression angle of the port plate is 3°?5° , and misalignment angle is 6° ?10° .In the engineering design in order to achieve the functional requirements of the piston pump, the pre-compression angle and misalignment angle of the port plate should be set by combining the pistons designed.According to the working principle of A10VNO axial piston pump under the control of pressure and flow, the integral model of pressure and flow axial piston pump is established by AMESim. Through configuring parameters reasonably and running the simulation model, the dynamic response characteristics of piston pump are simulated, and the influence of the spring stiffness and spool diameter of the flow control valve, the spring stiffness and piston diameter of the variable cylinder , and the diameter of damping hole on dynamic response and output flow pulsation of axial piston pump are carried out simulation research.