Study on the Flow in a Typical Seat Valve of Mobile Hydraulics

Vibrations induced by the internal flow in a typical seat valve used in mobile hydraulics are investigated under various extreme flow conditions. To reduce the noise associated with these vibrations, it is necessary to gain a thorough understanding of the flow in this particular hydraulic component and of the dynamic characteristic of the hydraulic system. The three-dimensional and turbulent flow in the valve is studied and characterized applying Computational Fluid Dynamics (CFD). Subsequently, dynamic phenomena, such as pressure pulsation, flow rate fluctuation, and body fixed acceleration, are analyzed from measurements on a hydraulic test assembly.

The combined method using CFD and direct measurements suggests itself as a very suitable approach to gain more understanding not only of the flow processes in the valve but also of the causes for the instability of the valve closing body.