表面微凹槽对机械密封性能的影响

The Sealing Performance of Mechanical Seals with Micro-grooves

采用FLUENT软件分析微凹槽结构对机械密封性能的影响,探讨凹槽深度比(凹槽深度与油膜厚度比值)、凹槽宽度比(微凹槽宽度与内环圆弧的直线长度比值)和凹槽长度比(微凹槽长度与圆环宽度比值)对开启力、液膜刚度、泄漏率的影响。结果表明:凹槽深度比、凹槽宽度比均存在一个最佳值使开启力和液膜刚度达到最大值,开槽深度与油膜厚度有着密切的关系;在凹槽宽度比一定时,凹槽宽度越大,开启力和液膜刚度也越大,而泄漏率基本保持不变,这表明毫米级宽度凹槽比微米级凹槽具有更好的密封性能;凹槽长度比越大,开启力和液膜刚度也越大,但是泄漏率也会同时增大。

The software FLUENT was used to analyze the effects on sealing performance of mechanical seals textured with micro-grooves. The effects of groove depth ratio （ ratio of the groove length to oil film thickness）, width ratio （ ratio of the groove width to length of inner arc straight line） and length ratio （ ratio of the groove length to the width of cirque） on sealing performance including opening force, leakage and stiffness of fluid film were discussed. The results show that groove depth ratio and width ratio can all be optimized to achieve max opening force and stiffness film, so the groove depth is closely related to film thickness. Under the same width ratio, opening force and film stiffness are increased as groove width and length increasing, while leakage ratio remains unchanged basically, which indicates that groove width of millimeter scale is better than micrometer scale in Sealing performance. The opening force and stiffness of fluid film will increase as length ratio increases, however leakage will also increase at the same time.