A Review on the Experimental and Numerical Studies of Flow in Liquid Ring Vacuum Pump

Abstract

The liquid ring vacuum (LRV) pump has been found to be very effective in evacuating toxic and inflammable gases in petroleum and refinery industries, medical applications, etc. The liquid inside the pump, as it rotates, interacts with the incoming gases which makes the flow behavior complex. The analysis of such multiphase flow behavior inside the pump becomes important to critically analyze the parameters which could affect the pump performance. These parameters are the evacuating pressure, seal liquid, impeller speed, ring shape, etc. Thus, in the past, several experimental and numerical studies have been reported in the literature focusing on the role of LRV parameters on its performance. So, in this paper, a review of these works is presented. Based on this review, it is found that (i) the efficiency of the liquid ring vacuum pump is low and varies for different application depending upon the nature of operation and pump capacity and (ii) the pump performance can be improved by modifying the geometrical design of the pump, operating parameters, and changing the types of operating liquid or varying the concentration of the mixed fluid.