基于湍流模型的螺旋槽机械密封端面流动特性分析  

Analysis of flow characteristics on the end face of spiral groove mechanical seal based on turbulence model

作　　者：谢星 张翊勋 丛国辉 刘杰 王永乐 丁思云 李鲲 XIE Xing;ZHANG Yixun;CONG Guohui;LIU Jie;WANG Yongle;DING Siyun;LI Kun(Hefei General Machinery Research Institute Co.,Ltd.,Hefei 230031,China;Hefei General Environmental Control Technology Co.,Ltd.,Hefei 230031,China;China Nuclear Power Engineering Co.,Ltd.,Shenzhen 518124,China)

机构地区：[1]合肥通用机械研究院有限公司,合肥230031 [2]合肥通用环境控制技术有限责任公司,合肥230031 [3]中广核工程有限公司,广东深圳518124

出　　处：《流体机械》2024年第9期31-38,共8页Fluid Machinery

基　　金：国家自然科学基金项目(52306040);中石化课题项目(322058);合肥通用机械研究院有限公司博士科技基金资助项目(2022011507)。

摘　　要：为了研究高转速液膜润滑螺旋槽机械密封湍流流动特性,基于k-ω湍流模型,计算了密封端面液膜相对速度、压力与湍动能分布,并分析了不同转速与膜厚下密封开启力、泄漏率与端面各流动熵产损失占比。结果表明:槽区位置流体速度小,密封堰区流体速度大;液膜压力分布呈周期性,在螺旋槽背面前1/2流向位置处产生了空化;螺旋槽入口湍动能较大,在螺旋槽深度方向上,越靠近密封动环螺旋槽底壁面,流体湍动能越大;流体膜区域总熵产损失明显大于螺旋槽区域,总壁面熵产损失占比≥60%,总湍流流动损失占比≥30%;随着转速增加,开启力与泄漏率增大,壁面熵产损失增加,直接熵产损失降低,当转速≥10000 r/min时,湍流与脉动熵产损失相对稳定,占比35.64%~37.24%;随着膜厚增加,开启力降低,泄漏率增大,壁面熵产损失先增大后减小再增大,直接熵产损失降低,当膜厚≥4μm时,湍流与脉动熵产损失相对稳定,占比40.26%~42.15%。研究结果可为高转速低能耗机械密封结构设计提供理论指导。To investigate the turbulent flow characteristics of high-speed liquid film lubricated spiral groove mechanical seal,the relative velocity,pressure and turbulent kinetic energy distribution of the liquid film were calculated based on k-ω turbulence model,and the opening force and leakage rate of the seal and loss proportion for each entropy production were analyzed.The results show that the fluid velocity is low at groove area and high at dam area.The liquid film pressure exhibits periodic distribution,and the cavitation areas occur at the front 1/2 flow direction position on back of the spiral groove.The fluid turbulent kinetic energy at the inlet of the spiral groove is relatively large.In the spiral groove depth direction,the closer it is to spiral groove bottom wall of the rotating ring,the larger the turbulent energy.The total entropy production losses in the lubricant film is significantly larger than that in the spiral groove,the proportion of total wall entropy production loss is larger than 60%,and the proportion of entropy production loss caused by turbulent flow is larger than 30%.As the rotating speed increases,the opening force and leakage rate increase,the wall entropy production loss increases,and the direct entropy production loss decreases.The turbulence and fluctuation entropy production losses are relatively stable when rotating speed is higher than 10000 r/min,the total proportion ranges from 35.64% to 37.24%.As the film thickness increases,the opening force decreases,the leakage rate increases,the wall entropy production loss first increases,then decreases and then increases,and the direct entropy production loss decreases.The turbulence and fluctuation entropy production losses are relatively stable when film thickness is larger than 4μm,the total proportion ranges from 40.26% to 42.15%.The research results can provide theoretical guidance for the structural design of high speed and low energy consumption mechanical seals.

关 键 词：机械密封 螺旋槽 湍流 流动损失 

分 类 号：TH133[机械工程—机械制造及自动化] TB42[一般工业技术]