Effects of boundary slip on performance of upstream pumping mechanical seal
Chen Huilong1, Xu Cheng1, Hu Ji2, Liu Zhibin 1, Zhao Binjuan1, Li Shulin3
1.School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Faculty of Civil Engineering and Mechanics, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 3.Nanjing Engineering Institute of Aircraft Systems, AVIC Jincheng, Nanjing, Jiangsu 211100, China
Abstract：To study effects of boundary slip on performance of upstream pumping mechanical seal, the geometric and computational models of fluid film are built. The Navier-Stokes equations of the fluid film flow are solved in Fluent by employing SIMPLEC algorithm and finite volume method. The boun-dary conditions are modified with the Navier linear slip model and the effects of boundary slip on the film pressure distribution, opening force, friction torque and fluid leakage are analyzed. The results show that the slip velocity has a greater influence than the location of slip occurrence. When the slip velocity is tinier, the results of simulation are almost the same as the data without slip, indicating the non-slip assumption for macro flow of a fluid is reasonable. However, when the slip is larger, the dynamic effect of fluid film is weakened and the opening force, friction torque and fluid leakage are decreased with the increasing slip velocity. Additionally, the reduction in both friction torque and leakage is more significant than that in opening force. If the opening force is smaller, the boundary slip should be avoided. If the opening force is large enough, the boundaries should be made super hydrophobic to introduce boundary slip effect so as to reduce the friction torque, eventually to save energy consumption. The results are useful to the design of an upstream pumping mechanical seal.
陈汇龙, 徐成, 胡吉, 刘志斌, 赵斌娟, 李述林. 边界滑移对螺旋槽上游泵送机械密封性能的影响[J]. 排灌机械工程学报, 2015, 33(1): 55-60.
Chen Huilong, Xu Cheng, Hu Ji, Liu Zhibin , Zhao Binjuan, Li Shulin. Effects of boundary slip on performance of upstream pumping mechanical seal. Journal of Drainage and Irrigation Machinery Engin, 2015, 33(1): 55-60.
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