Cavitation and Loss Reductions of Butterfly Valve by Modifying the Shaft Boss Profile

축 보스 형상 변형을 이용한 버터플라이 밸브의 캐비테이션과 유동손실 감소

In this paper, a numerical investigation of three-dimensional, two-phase flow field around a butterfly valve is conducted. The butterfly valves that have different opening angles, $10^{\circ}{\sim}90^{\circ}$, and two profiles of the shaft boss are compared with various cavitation numbers and Reynolds numbers. This paper focused on the flow analysis in the original butterfly valve and new design butterfly valve in order to decrease cavitation and loss. It is found that the butterfly valve with a cone-type shaft boss greatly reduces the cavitation and loss, compared to the original shaft boss by 20${\sim}$30%.