Numerical and experimental investigation on heat transfer characteristics of flexible bristle brush seal

LI Shuang-xi1, MA Yu-hu1, ZHANG Shan-yu2, SHA Lian-xiang1, CHEN Kun-yi1, LIAO Hao-ran1
(1.School of Electrical and Mechanical Engineering, Beijing University of Chemical Technology, Beijing
100029, China; 2.China Aerospace Standardization Research Institute, Beijing 100071, China)

Abstract: Aiming at the problems of the machine performance which was affected by the friction heat generation, the local overheating of the bristle pack, and the heat transfered into the bearing cavity; the heat generation, heat dissipation and heat insulation performance of flexible bristle brush seal were investigated. Numerical models of large interference flexible bristle brush seal and classic metal bristle brush seal were established for CFD porous media, the friction heat generation performance, the heat transfer performance along the plate, and the heat insulation performance of preventing heat from entering the bearing cavity were analyzed. The influence of working condition parameters and structure parameters on the heat-insulation performance was explored, the frictional force and frictional heat generation of flexible bristle brush seal were tested. The results indicate that friction heat generation of carbon fiber brush seal is lower, heat transfer efficiency of carbon fiber bristles and plate is higher, heat insulation performance of carbon fiber brush seal is better. Heat flow increases under the conditions of large pressure difference and high temperature, different speed ranges have different effects on heat flow, increasing the bristles pack thickness or decreasing the front and back plate clearance can improve the heat insulation performance. The experimental results are in good agreement with the numerical results, with an error of 9.4%.
Key words: flexible bristle brush seal; heat transfer characteristics; numerical analysis; experimental investigation