Numerical and Experimental Study On the Influence of Honeycomb Bushing Wear On the Leakage Flow Characteristics of Labyrinth Seal

Abstract

Honeycomb bushing wear has a significant effect on the leakage characteristics of the labyrinth seal. In this paper, four kinds of honeycomb bushing labyrinth seals were designed and processed. The leakage characteristics of honeycomb bushing labyrinth seal were studied experimentally under different inlet and outlet pressure ratios and sealing clearance conditions. At the same time, the numerical model of honeycomb bushing labyrinth seals were established, and the influence of honeycomb bushing wear on the flow field characteristics of labyrinth seals was analyzed by numerical simulation. The existing leakage formula was modified by the correction coefficient method. The results show that the leakage of four kinds of honeycomb bushing labyrinth seals increases with the increase of pressure ratio and sealing clearance, and the sealing effect of unworn honeycomb bushing labyrinth seal is the best. With the increase in wear depth, the leakage of the honeycomb bushing labyrinth seal increases, and the maximum leakage can be increased by 59.59 %. The wear groove weakens the throttling effect of the labyrinth, causing the leakage of the seal to increase. The increase of the depth of the wear groove changes the flow area and the direction of the jet, so that the leakage increases slightly. The theoretical formula of leakage is corrected by the correction coefficient method. The value calculated by the corrected theoretical formula of leakage is in good agreement with the experiment, and the error is within 5%. It meets the practical application of the project.