Abstract:A honeycomb seal installed between two parallel flat plates was used as an analytical model; the threedimensional flow in the seal was solved numerically according to the Navier-Stokes equations and Vreman subgrid stress model to investigate the leakage characteristics and sealing mechanism in honeycomb seals for water. The finite volume method was used to discretize the Navier-Stokes equations and the secondorder upwind scheme and the secondorder central scheme are applied to the convection and diffusion terms in the equations, respectively. The leakage flow rates through the honeycomb with different sizes of cells were obtained by means of numerical computation and compared with those in a corresponding labyrinth seal; eventually, the leakage characteristics and sealing mechanism were discussed. The results show that the honeycomb seal has better sealing performance than the labyrinth seal, a honeycomb with cells of 6 mm radius and 4 mm depth achieves the lowest leakage flow rate, causing the best sealing effect. Also, the leakage flow rate increases approximately linearly with increasing pressure difference across the inlet and outlet of the seal; however, the leakage flow rate remains nearly constant when the plate moving speed varies. Through further exploring the flow pattern in the honeycomb seal, it was observed that strong vortices have been generated in the honeycomb cell and consume the kinetic energy of stream. Such a flow pattern is mainly responsible for pressure drop and throttling effect in the seal.
王文全, 张立翔, 闫妍. 蜂窝密封的水封特性[J]. 排灌机械工程学报, 2013, 31(3): 248-252.
WANG Wen-Quan, ZHANG Li-Xiang, YAN Yan. Investigation into leakage characteristics of honeycomb seals for water. Journal of Drainage and Irrigation Machinery Engin, 2013, 31(3): 248-252.
[1]晏鑫, 李军, 丰镇平. 蜂窝密封内流动传热及转子动力特性的研究进展 [J]. 力学进展, 2011, 41(2): 201-216.Yan Xin, Li Jun, Feng Zhenping. Review of the discharge, heat transfer and rotordynamic characteristics of honeycomb seals[J]. Advances in Mechanics, 2011,41(2): 201-216. (in Chinese)[2]李军, 邓清华, 丰镇平. 蜂窝汽封和迷宫式汽封流动性能比较的数值研究[J]. 中国电机工程学报, 2005, 25(16): 108-111,131.Li Jun, Deng Qinghua, Feng Zhenping. Comparison of the flow characteristics for the honeycomb and labyrinth seal using numerical simulation [J]. Proceedings of the CSEE, 2005, 25 (16): 108-111,131. (in Chinese)[3]张强, 何立东. 蜂窝密封动力特性系数的计算方法[J]. 中国电机工程学报, 2007, 27(11): 98-102.Zhang Qiang, He Lidong. Study on calculation of the dynamic coefficients of honeycomb seals [J]. Proceedings of the CSEE, 2007, 27 (11): 98-102. (in Chinese)[4]伍伟, 何立东, 俞龙,等. 铝蜂窝密封结构设计及性能研究[J]. 中国电机工程学报, 2010, 30 (17): 67-73.Wu Wei, He Lidong, Yu Long, et al. Research on structure design and sealing performance of aluminium honeycomb seals [J]. Proceedings of the CSEE, 2010, 30 (17): 67-73. (in Chinese)[5]何立东, 尹德志, 李承曦, 等. 水轮机应用蜂窝密封的吸水和减振模型试验[J]. 排灌机械工程学报, 2010, 28(3): 215-218.He Lidong, Yin Dezhi, Li Chengxi, et al. Simulation experiment on water pumping and vibration suppression of Francis turbine applying honeycomb seals[J]. Journal of Drainage and Irrigation Machinery and Engineering, 2010, 28 (3): 215-218. (in Chinese)[6]李金波, 何立东. 蜂窝密封流场旋涡能量耗散的数值研究[J]. 中国电机工程学报, 2007, 27(32): 67-71.Li Jinbo, He Lidong. Energy dissipation of vortexs in honeycomb seals using numerical simulation [J]. Proceedings of the CSEE, 2007, 27(32): 67-71. (in Chinese)[7]He Kun, Li Jun, Yan Xin, et al. Investigations of the conjugate heat transfer and windage effect in stepped labyrinth seals [J].International Journal of Heat and Mass Transfer, 2012, 55 (17/18):4536-4547.[8]Vreman A W. An eddyviscosity subgridscale model for turbulent shear flow: Algebraic theory and applications[J]. Physics of Fluids, 2004, 16(10): 3670-3681.[9]You D, Moin P. A dynamic globalcoefficient subgridscale eddy viscosity model for largeeddy simulation in complex geometries[J]. Physics of Fluids, 2007, 19(6): 065110.[10]You D, Moin P. A dynamic globalcoefficient subgridscale eddyviscosity model for largeeddy simulation of turbulent scalar transport in complex geometries[J]. Physics of Fluids, 2009, 21(4): 045109.