Abstract:

The liquid film phase change phenomenon not only changes the lubrication state of the end face, but also has a significant influence on the sealing performance and stability. The governing equations are discretized using the finite volume method. The influence of the structure parameters of spiral groove and the sealing condition on the sealing performance and phase change rate were studied. Results show that the opening force and leakage rate increase with the increase of the spiral angle, the number of grooves, groove depth, the pressure difference and the rotation speed; increase first and then decreases with the increase of the ratio of groove width in radial direction to surface width and the ratio of groove width to dam width, and take the maximum value when the ratio of groove width in radial direction to surface width ζ=0.5 and the ratio of groove width to dam width φ=0.7. The phase change rate increases with the increase of spiral angle and rotating speed, decreases with the increase of the number of grooves, groove depth, the pressure difference and the ratio of groove width to dam width, decreases first and then increases with the increase of the ratio of groove width in radial direction to surface width, and take the minimum value when the ratio of groove width in radial direction to surface width ζ=0.8. The phase transition process can be effectively inhibited by reasonable selection and combination of the parameters. The sealing performance can be improved by using the phase change phenomenon while ensuring the stability of the sealing operation.

Key words: phase change, liquid film seal, sealing performance, finite volume method

摘要：

液膜相变现象不仅改变了端面润滑状态，而且对密封性能及稳定性有着显著的影响。使用有限体积法对控制方程进行离散，研究了螺旋槽结构参数与密封工况参数对密封性能及液膜相变率的影响。结果表明：开启力与泄漏量随螺旋角、槽数、槽深、压差、转速的增大而增大，随槽面宽比、槽台宽比的增大先增大后减小，分别在槽面宽比ζ=0.5与槽台宽比φ=0.7时取到最大值。相变率随螺旋角、转速的增大而增大，随槽数、槽深、压差、槽台宽比的增大而减小，随槽面宽比的增大先减小后增大，在槽面宽比ζ=0.8时取最小值。通过对各参数合理地选择与组合，可以有效地抑制相变进程，进而在保证密封运行稳定的同时利用相变现象提高密封性能。

关键词: 相变, 液膜密封, 密封性能, 有限体积法