Computational fluid dynamics of axial piston pumps´flow characteristics and improvement of their speed limit
Research Task/Objectives
Rotational speed limit: Experiment and simulation
At high rotational speeds of axial piston pumps, cavitation effects cause the partial filling of the cylinders with gas. The consequence is a flowrate breakdown and thus a limitation of the pump’s power density as well as its rotational speed.
Countermeasures that have been derived using partial models in previous projects are being merged in a holistic CFD model of the pump. Furthermore, speed limiting flow effects that will only occur using interacting part models are being identified, and further countermeasures are being derived in order to increase the pump’s speed limit and thereby its power density.
Approach/Results
Reduction of speed limiting cavitation effects
The flow characteristics simulated by means of CFD are being validated using test bench measurements.
Afterwards, the speed limiting cavitation effects are being identified and systemized. Based on that, constructive countermeasures are being derived and those from previous projects are being taken into account. At the current project stage, virtual tests show an increase of the pump’s speed limit of 8.6 % using a combination of various constructive improvements.
The presented research activities are part of the project "speed limit of piston pumps" (Ref. No. 703070). The authors would like to thank the Fluid Power Research Fund of the VDMA for the funding and support.