Research On Fluid Noise Of Swash Plate Axial Piston Pump Based On Joint Simulation

Axial piston pump is one of the commonly used core power components in hydraulic transmission systems,with many advantages such as wide applicability,small volume,high flow rate,and long service life.It has been widely used in large-scale industrial fields such as aerospace,metallurgical machinery,and ocean transportation.With the continuous development of the usage environment of axial piston pumps towards high temperature,high pressure,and high speed,the noise problem is becoming increasingly prominent.Fluid noise,as one of the main noise sources of axial piston pumps,seriously endangers the normal operation of hydraulic systems.This article takes a certain type of swash plate axial piston pump as the research object.A three-dimensional model is established using Soildworks software and fluid domain extraction is performed.Based on numerical simulation theory,CFD software is used for simulation calculation to obtain the flow and pressure pulsation characteristics of its internal flow field,and theoretical analysis is conducted.Finally,the flow field data is imported into the acoustic software through joint simulation,Obtain the spectral information and total sound pressure level data of the plunger pump under different operating conditions using the Lighthill acoustic analogy method,and study the impact of different port plate structures on noise by changing the width angle of the triangular groove.The main research work of this article is as follows:(1)The internal transient flow field of the axial piston pump is numerically simulated by Fluent software.By selecting the mixed model,the standard k-model and the Schnerr Sauer cavitation model,the Control variates is used to analyze the three factors of the plunger speed,oil temperature and oil void fraction of the plunger pump under variable working conditions.The flow and pressure information of the plunger pump under different conditions are obtained and the mechanism analysis is carried out.(2)Import the flow field information into the acoustic software,model the acoustic grid and set the conditions.Use ICFD conversion to obtain the distribution of body and surface sound sources of the axial piston pump at different frequencies.Set corresponding monitoring points in the flow field model and sound field model,obtain the comparison results of the pressure pulsation rate at the monitoring point and the noise at that point,and analyze the cause of formation.Thus,obtain the results of the axial piston pump under the three different working conditions mentioned above Noise information at different locations.(3)Use 3D software to reset the width angle of the triangular groove,analyze the flow pulsation and noise situation of the axial piston pump under different flow area conditions,compare and analyze the impact of different port plate structures on flow pulsation and noise.Through this study,it was found that increasing the speed of a plunger pump or reducing its oil temperature within a certain range can lead to an increase in its pulsation rate,resulting in significant fluid noise;The increase in oil void fraction will lead to cavitation phenomenon,exacerbating the generation of cavitation noise.The total sound pressure level at the outlet of the plunger pump should be higher than the total sound pressure level at the inlet,with a difference of approximately 10 d B in value;The noise generated at the pre boost point of the distribution plate should be between 2-7d B higher than that at the pre boost point;In the triangular groove width angle structures of 30°,50°,and 70°,the flow pulsation and noise are minimized when the width angle is 50°,indicating that noise reduction can be achieved by changing the flow area under certain circumstances.