CONTACT TEMPERATURE ESTIMATION FOR INTERFERENCE, DUAL BRUSH SEALS

摘要

It is generally accepted that wear in brush seals is a major concern that needs to be addressed. Although the contact temperature is an important parameter of the wear process, few attempts have been made to measure or to model it. In a recent paper, Pascovici & Cicone proposed a simplified elasto-thermo-triblogical model for brush seals based on classical fin model for heat transfer in the bristle. Their analytical solution allows to estimate the contact temperature for interference brush seals assuming that all the heat generated by dry friction (unlubricated contact) at the bristle tip is rejected by convective heat transfer between the bristle and the sealed gas. In the present paper this model is extended to include heat partition between the bristle pack and the shaft. Closed form analytical solutions for heal partition coefficient and maximum contact temperature are proposed. A numerical example is given, showing the importance of heat transfer calculation. The model is applicable to interference, dual brush seal arrangements, a solution currently used in turbomachinery,