CIESC Journal ›› 2022, Vol. 73 ›› Issue (4): 1683-1694.DOI: 10.11949/0438-1157.20211721

• Surface and interface engineering • Previous Articles     Next Articles

Turbulence characteristics of compliant foil gas seal considering surface roughness

Xueliang WANG(),Meihong LIU(),Zhongfen XIONG,Xin LI   

  1. Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
  • Received:2021-12-02 Revised:2022-01-19 Online:2022-04-25 Published:2022-04-05
  • Contact: Meihong LIU

考虑表面粗糙度的柔性箔柱面气膜密封紊流特性分析

王学良(),刘美红(),熊忠汾,李鑫   

  1. 昆明理工大学机电工程学院,云南 昆明 650500
  • 通讯作者: 刘美红
  • 作者简介:王学良(1993—),男,博士研究生,1243604619@qq.com
  • 基金资助:
    昆明理工大学分析测试基金(2020P20173103001);国家自然科学基金项目(51905480);宁波市自然科学基金项目(2019A610161)

Abstract:

Compliant foil gas seal is a new structural form of cylindrical gas film seal. This structure can be applied in hydrogen compressor. The combination of gas film dynamic and the compliant foil achieves high performance seal. In order to analyze the influence of surface topography and turbulence on sealing characteristics of compliant foil gas seal, this paper solves the Reynolds equation by periodic condition. This equation includes the factor of surface roughness. The result is compared with the experimental. The influence of surface roughness on compliant foil gas seal includes leakage, gas force, gas stiffness and sealing hysteresis. Meanwhile, the influence of surface roughness on the cycle test of compliant foil gas seal is observed. The results show that the factor of surface roughness has important effect on the leakage and seal hysteresis. With the surface roughness and speed increases, the mid-surface pressure fluctuation largely. Meanwhile, the leakage and the gas force increases obviously with the increase of surface roughness, but the gas stiffness decreases. This casues the instability of gas film seal. Under the full cycle test, there is sealing hysteresis in the gas film seal. The increase of surface roughness leads the increase of the sealing hysteresis energy. Moreover, there is anti-hysteresis phenomenon under different surface roughness. This is caused by elastic element and the transient variation of friction and speed. Therefore, it is important to control the surface roughness for compliant foil gas seal.

Key words: compliant foil gas seal, surface roughness, seal hysteresis, turbulent characteristics, cycle test

摘要:

柔性箔柱面气膜密封是一种可适应氢气压缩机高速转子大变形的密封结构新形式,该密封结合了气膜楔形动压和箔片柔性来实现高性能密封,但是目前高速环境下紊流与表面形貌的相互关联机制对柔性箔柱面气膜密封性能的影响规律缺失,因此本文以表面粗糙度为主要考量因素进行周期性分析计算,并设计了不同表面粗糙度变化对高转速柔性箔密封性能启停循环实验的影响。研究结果表明,当表面形貌不规则度越高,中性面产生的压力波动越大;泄漏率和气浮力随着表面粗糙度的增加而增加,动态特性系数气浮刚度则呈下降趋势,因而气膜稳定性降低;循环周期实验下,气膜密封存在迟滞现象,表面形貌的不规则越高,密封迟滞能越大,另外,受弹性元件、系统摩擦与转速瞬态变化的影响,柔性箔柱面气膜密封会出现反迟滞现象。

关键词: 柔性箔柱面气膜密封, 表面粗糙度, 密封迟滞, 紊流特性, 循环周期实验

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