Abstract:An analytical pressure distribution function in the gas film is obtained by using the PH linearization and an iterative method without considering deformation of the seal rings based on the Reynolds equation under the sliding boundary conditions. From the equation relating to entropy change of microfluid flow in the spiral grooves, the temperature field in the gas film was obtained. The temperature distribution in the gas film under the different polytropic exponents was analyzed by considering the process of entropy change of the fluid in the spiral groove. The thermoelastic deformation of the seal rings and an approximate analytical formula for the gas film thickness were obtained for different polytropic exponent, the pressure distribution for the thermoelastic deformation was worked out as well based on the generalized Reynolds equation. The leakage through the seals was predicted and compared with the theoretical one without deformation for different polytropic exponents. The results demonstrated that the highest temperature in the film appears inside the seals as a fluid flows inwards and the most significant deformation occurs there. The leakage was increased with deformation, eventually affecting the sealing performance. The leakages under different polytropic exponents were much closer to the experimental measurements. The results can be used as a theoretical basis for optimization design of dry gas seals.
韩明君, 李有堂, 苏虹, 丁雪兴, 俞树荣. 干气密封螺旋槽内润滑气膜的热力过程[J]. 排灌机械工程学报, 2012, 30(4): 457-462.
Han-Ming-Jun, LI You-Tang, SU Hong, DING Xue-Xing, YU Shu-Rong. Thermodynamic process of lubricating gas film in dry gas seals with spiral grooves. Journal of Drainage and Irrigation Machinery Engin, 2012, 30(4): 457-462.
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