Experimental Research of Unsteady Flow around an Oscillating Control Valve Plug Model Using a Magnetic Suspension and Balance System

Abstract

The purpose of this study is to elucidate an unsteady phenomenon related to a control valve in the hydraulic equipment. Experiments on a control valve plug model with no support were conducted by using a Magnetic Suspension and Balance System (MSBS). The fluid force and the differential pressure between upstream and downstream acting on the valve model was measured by steady–state tests and oscillating tests. The fluid force and the differential pressure changed to depend on the flow rate and the gap distances. The flows are quasi-steady at frequencies 0.25 ~ 1.0 Hz by comparing the results of steady–state tests and oscillating tests. These results show that the evaluation of a control valve plug with MSBS will be beneficial to design the hydraulic equipment.