Flow characteristics of throttle valve with sharp-edged seat

A throttle valve, of which the flow characteristics is one of the important factors, is a typical hydraulic element for controlling pressure or flow in hydraulic actuation systems. This paper represents a new method to investigate the flow characteristics of water hydraulic poppet valve with sharp-edged seat. Based on previous studies of pressure field inside poppet valve, a simplified model is developed to describe the pressure distribution on the spool conical surface. The static flow force acting on the spool is investigated by utilizing the pressure distribution and the momentum theorem. The flow-pressure equation and the flow coefficient are modeled based on the equivalence of the two methods. Experimental studies are carried out to investigate the flow characteristics and comparison analyses are made between the models and the experiments. The results show that the flow characteristics of poppet valve is highly affected by the inlet/outlet conditions, openings and spool taper angles and can be expressed considerably by the models.