离心式气密封在轴承油雾治理中的应用及流场分析  

Application of centrifugal gas seal in bearing oil mist control and its flow field analysis

作　　者：田仁斌 张承俊[1] 苏纪成 陈晓龙[1] 魏学锋[1] TIAN Renbin;ZHANG Chengjun;SU Jicheng;CHEN Xiaolong;WEI Xuefeng(China Yangtze Power Co.,Ltd.,Yichang 443000,China)

机构地区：[1]中国长江电力股份有限公司,湖北宜昌443000

出　　处：《人民长江》2022年第4期215-220,共6页Yangtze River

基　　金：中国长江电力股份有限公司Ⅰ类自主科研专项经费项目(1517020001项6.24)。

摘　　要：为有效解决大型水轮发电机组推力轴承普遍存在的油雾污染问题,基于“疏”代替“堵”的理念,提出了一种离心式气密封结构,并在溪洛渡电站某台机组上安装应用。该结构在机组大轴上安装了离心式叶片,叶片随轴转动,在流道内形成高速高压的气流,外溢的油雾则随气流进入蜗壳流道,最后被油雾吸收系统带走,阻止了油雾被转子支臂下方的负压吸走,油雾治理效果良好。此外还采用计算流体力学软件对该结构的内部流场进行了三维数值模拟,分析了叶片的气动性能及内部流场规律,计算结果与现场试验结果一致,验证了计算方法的可靠性。研究结果为大型水轮机组轴承油雾治理提供了一种新的解决思路,也为气密封的研究及优化设计提供了一种参考。To solve the general oil mist pollution in thrust bearings of large hydro-generator units, based on the theory that dredging can obtain better effect than blocking, a new centrifugal gas seal structure was proposed, which was verified in one unit of Xiluodu Hydropower Station.In this structure, centrifugal blades were installed on the main shaft of the unit, and it could turn round with the shaft to generate high speed and high pressure airflow in the entire flow channel.The spilled oil mist will be brought into the volute channel by the airflow above and be absorbed by the oil mist system finally.So the oil mist was prevented from being sucked away by the negative pressure under the rotor hub arm and oil pollution was effectively controlled.In addition, the CFD software was used to conduct three-dimensional numerical simulation on the internal flow field of the centrifugal air seal.The aerodynamic performance of the blades and the internal flow field law were discussed.The simulation results were consistent with the experiment data, which verified the reliability of numerical simulation method.The research results can provide a new solution for bearing oil mist control of large hydro-generator units, and a reference for the research and optimization of gas seals.

关 键 词：油雾治理 离心式气密封 数值模拟 流场分析 水轮发电机组 溪洛渡水电站 

分 类 号：TV734[水利工程—水利水电工程]