Effects of throttling windows on cavitation flow of sleeve control valve

The control valve is the key equipment in nuclear power plants, which is mainly used to control the fluid flow, and essential for the safe operation of nuclear power plants. Cavitation is one of the most common phenomenon inside control valves, which will not only generate noise and vibration, but also reduce the service life of control valves. In this paper, the effects of throttling windows numbers and flow directions on the cavitation characteristics of a typical sleeve control valve are analyzed by numerical simulation. Results show that the vapor volume of 2, 4, 6, 8 throttling windows when fluid flows in the forward direction are 33.83, 39.25, 71.56, 59.34 times of the vapor volume in the backward direction respectively, which means increasing the throttling windows number can greatly reduce the vapor volume. Meanwhile, the vapor distribution is significantly different under different flow directions. The energy loss is more serious when the fluid flows in backward direction. Therefore, the erosion and abrasion of the valve body caused by the fluid impact can be reduced by changing the flow direction of the fluid from forward to backward and increasing the throttling windows number. This paper analyzes the cavitation characteristics of the control valve based on the switching conditions and discusses the mechanism of the working conditions and structural parameters on the cavitation characteristics, which is of significance for the anti-cavitation design of control valves.