Optimization of cross angle based on the pumping dynamics model

The single cylinder and multi-cylinder pumping dynamics model of a swash plate piston pump were improved. Particular attention has been paid to the design influences of key parts of the valve plate such as relief groove, pre-compression/expansion and fluid inertia effect of the unsteady flow. Some important parameters, such as the discharge area, discharge coefficient, fluid bulk modulus, were especially analyzed using numerical methods or by experiment-based estimation. Consequently, the mathematical results of pressure pulsation and flow ripple agree well with experimental results from the test-rig of the flow ripple. Therefore, the cross angle and the pre-compression angle of the valve plate was optimized, based on the pumping dynamics model. Considering both the flow ripple and the cylinder pressure of the pump, the cross angle is set to be 2.2° to 2.7° with a pre-compression angle of 1.7° to 2.2°, so the pumping dynamics character can obtain the best result.