Experimental study on the effect of bubble cluster shape on cavitation in water hydraulic valve

Abstract

The experimental studies presented in this paper attempt to study the cavitation in water hydraulic valve from the perspective of the bubble cluster shape and its change over time. Based on the 3-D vision method of combining a high-speed camera with 5 plane mirrors, the characteristics of the bubble cluster shape with an opaque object are discussed in a three dimensional approach. By applying the bionic structure at the valve seat which changes the fluid flow performance, the shape features of the bubble cluster, including bubble number, contour and equivalent density in vertical direction, were altered. Taking into consideration the bubble cluster flow pattern and the development process from generation to collapse of the bubble, the degree of cavitation of the constraint space inside the valve was analyzed and estimated. The analysis compared two sets of experiment and testified the efficiency of the bionic jet hole structure on valve seat.