Characteristics of cavitation evolution through a butterfly valve under transient regulation

As the key control equipment for the transmission of the fluid medium, butterfly valves are widely used in transmission systems of media in the energy, chemical industry, metallurgy, aerospace engineering, and other fields, playing an important role in the stability and reliability of system operation. When the flow cross section suddenly changes, the pressure rapidly decreases the downstream, leading to cavitation in butterfly valves. Cavitation causes serious erosion and damage in the valve core and pipeline surface, resulting in leakage and noise problems in butterfly valves, which seriously affects the regulation performance and lifetime of butterfly valves. In this study, numerical analyses are conducted to investigate cavitation evolution at the transient regulation of a butterfly plate through a butterfly valve model. Moreover, the effects of the valve opening degree and rotating speed on the cavitation volume and distribution, rate of cavitation volume change, growth-collapse rate of cavitation, and correlation between cavitation and vortex in the opening and closing processes of butterfly valves are investigated. Due to the influence of transient regulation and flow hysteresis, the characteristic parameters and evolution of cavitation exhibit different behaviors in the opening and closing processes of butterfly valves.