Cavitation effect and leakage control mechanism of reverse spiral grooves mechanical end face seals

doi:10.11949/j.issn.0438-1157.20170726

Abstract

Abstract:

The Reynolds equation of a reverse spiral groove mechanical end face seals was solved based on the JFO cavitation boundary condition by the Stream-Upwind/Petrov-Galerkin (SUPG) finite element method. The cavitation effect of the reverse spiral grooves was investigated. A novel reverse-spiral-grooved seal end face combined with forward-spiral grooves was proposed. The sealing performance under the different operating conditions was analyzed. The results show that the liquid film in grooved zones is prone to cavitation for the reverse spiral groove end face seal. The cavitation zones significantly affect the flow field distribution of the fluid film. The fluid at the inner side can be absorbed into the cavitation zones due to the pressure difference between the cavitation zones and the inner side. The novel seal end face combines the leakage control effect of the reverse spiral grooves and the hydrodynamic effect of the forward spiral grooves, and shows good upstream pumping capacity and load carrying capacity.

Key words: finite element method, spiral groove, cavitation effect, mechanical seal, upstream pumping effect

摘要：

针对机械端面密封的反向螺旋槽结构，基于遵循质量守恒的JFO空化边界条件，采用SUPG有限元方法求解Reynolds方程，研究了反向螺旋槽的空化效应，基于此，提出了一种新型的正反向螺旋槽组合端面密封结构，分析了不同工况条件下的密封性能。结果表明：反向螺旋槽区域易发生液膜空化，周期性分布的空化区会显著影响端面流场，空化区的低压力可将内径侧流体抽吸到密封端面，实现上游泵送。新型正反向螺旋槽端面密封结构结合了反向螺旋槽产生的泄漏控制作用和正向螺旋槽产生的流体动压效应，同时具备良好的上游泵送能力和动压承载能力。

关键词: 有限元方法, 螺旋槽, 空化效应, 机械密封, 上游泵送效应

CLC Number:

TH117.2

MA Xuezhong, MENG Xiangkai, WANG Yuming, ZHAO Wenjing, SHEN Mingxue, PENG Xudong. Cavitation effect and leakage control mechanism of reverse spiral grooves mechanical end face seals[J]. CIESC Journal, 2018, 69(4): 1558-1568.

马学忠, 孟祥铠, 王玉明, 赵文静, 沈明学, 彭旭东. 机械端面密封反向螺旋槽空化效应与泄漏控制机理[J]. 化工学报, 2018, 69(4): 1558-1568.

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