Experimental and Numerical Study of Cavitation Inside Sharp-Edged Multi-Hole Orifice Plate

Abstract

Cavitation can be useful in many occasions, for example, it can be adopted to improve the mass and heat transfer of the solution and it can also be used during the wastewater treatment. Among the ways to generate cavitation in hydrodynamic devices, the sharp-edged orifice is often used because it has a simple structure and the tube that has multi-holes orifice plate is more likely to generate cavitation. In this paper, experiment and computational fluid dynamic (CFD) method are carried out, the flux of the test tube is recorded during the experimental process, and the cavitation model used in the numerical study is validated by comparing the simulated results with the experimental results, then triangular, rectangular, and circular shape of holes and different kinds of distributions of holes such as circular and rectangular distributions are numerically studied. The vapor volume fraction is visualized to find out the effects of holes shape and arrangement on cavitation intensity. Besides, study focusing on the inlet pressure is achieved using CFD simulations, and the cavitation number is calculated under different cases to find out their effects on cavitation intensity. It can be concluded from the obtained results that cavitation number decreases with the increase of pressure drop, and under a certain value of pressure drop, the orifice plates with circular holes have the minimal cavitation number and maximal cavitation intensity. When the holes are circular arrangement, the orifice plates with circular and triangular holes has higher cavitation intensity, and when inlet pressure is large enough, different arrangement and shape of holes barely affect the cavitation intensity.