Axial piston pumps have been widely used as power sources for hydraulic systems, but studies on the fluid flow within the pump have usually been performed by using 1-D analysis due to the difficulties in considering the fluid compressibility, high-speed revolution, variation of the flow rate, and complicated geometry.
To simulate the flow field before manufacturing, it is useful to develop a numerical method for flow-analysis. Using a commercial code (CFX), developed for flow-analysis, useful informations for pump design could be obtained. Three-dimensional analysis has been performed to investigate the flow field between rotating part and fixed part especially for pressure distributions. To improve the convergence and robustness of the simulation model, a new grid system was constructed by adapting hexahedron-type grid. Furthermore, an empirical formula was employed to describe the relationship between the oil density and pressure.
In this study, pump characteristics and performances were investigated for varied pressures and flow rates which occurred during actual operating conditions. Pressure drop at the suction port was calculated to be about 0.0542 . Pressure pulsation at rated load and rated pressure in the piston was within the allowable range of ±6%.
The results of this study can be used to understand the performance characteristics of the pump when designing a new pump.