Analysis on steady fluid dynamics of cylindrical gas seal by CFD
SUN Junfeng1, LIU Meihong1, LI Yuxian1, SU Zehui2, KANG Yuchi1
1.Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming, Yunan 650504, China; 2.Lanshi Energy Equipment Engineering Institute, Lanzhou, Gansu 730050, China
Abstract：In order to explore the effect of groove structure on the sealing performance of a new type cylindrical gas seal, in the paper, the static pressure distribution, fluid velocity distribution and gas shear stress distribution in the sealing film are analyzed and compared between two structures by using the CFD software. The two structures include ordinary flat and T-groove floating rings. The results demonstrate that a large film pressure variation is found in the circumferential direction in the ordinary flat floating ring seal, specially, the highest pressure is in the area with the minimum film thickness or vice versa because of the fluid hydrodynamic effect generated by the eccentric rotation of the ring. For the T-groove floating ring, a large film pressure is in the groove and its root, and the maximum pressure is higher than in the ordinary floating ring film. Because every groove can produce a hydrodynamic effect, the film pressure not only exhibits several peaks in the circumferential direction, but the number of pressure peaks is equal to the number of grooves. Compared with the ordinary floating ring, the fluid velocity in the T-groove floating ring film is larger than in the ordinary flat ring film due to even strong hydrodynamic effect generated by the grooves. The maximum shear stress occurs in the range with the minimum film thickness in the ordinary flat ring film, in the T-groove ring film, however, the maximum shear stress is located at the minimum film thickness and in the dam area of groove root; further its value is larger than the former.
孙军锋, 刘美红, 李遇贤, 苏泽辉, 康宇驰. 基于CFD柱面气膜密封静态力学性能分析[J]. 排灌机械工程学报, 2017, 35(11): 968-974.
SUN Junfeng, LIU Meihong, LI Yuxian, SU Zehui, KANG Yuchi. Analysis on steady fluid dynamics of cylindrical gas seal by CFD. Journal of Drainage and Irrigation Machinery Engin, 2017, 35(11): 968-974.
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