Investigation Into the Effects of Index Angle on Fluidborne Noise and Structureborne Noise of a Tandem Axial Piston Pump

Abstract

High noise level is one of the dominant drawbacks of axial piston pumps which are widely applied in industry, mobile and aircraft applications. Lots of early studies focused on the noise reduction of a single pump, while this study focuses on investigating the noise characteristics of a tandem axial piston pump. We develop a lumped parameters/finite element (LP/FE) model of an axial piston pump for fully capturing its fluidborne noise and structureborne noise characteristics. We consider fluid compressibility and main leakages in the LP model which is verified by a comparison of discharge flow rate with experimental tests built based on the secondary source method. The FE model was developed on the basis of actual pump with excitation forces obtained from the LP model. The effects of index angle in a tandem pump to the fluidborne noise and structureborne noise are analyzed with the LP/FE model, respectively. A sensitivity analysis is carried out in a wide range of discharge pressures and displacements at a fixed revolution speed, further. Results indicate that fluidborne noise is reduced by 52.1%, whilst structureborne noise is increased by 2 dB(A) with an index angle of 20° to zero, respectively.