液膜密封润滑状态转变及性能分析

Lubrication State Transition and Performance Analysis of Liquid Film Seal

以螺旋槽液膜密封为研究对象,求解考虑流量因子的平均雷诺方程,研究工况参数和结构参数对密封端面润滑状态转变规律的影响。结果表明:随着转速升高,液膜厚度与液膜承载系数逐渐增加,粗糙峰接触力不断减小至消失,实现摩擦副分离;低黏度介质对临界转速的影响显著;随着压差的增大,临界转速与闭合力均呈线性增大的趋势;临界转速随槽深、螺旋角增大而增大,随槽数、槽坝比增大而减小,结构参数中槽深对其影响最为显著,为提高润滑状态转变能力,建议取槽深3~7μm,螺旋角14°~18°,槽数16~24,槽坝比2/3~5/6。

Taking the spiral groove liquid film seal as the research object, the average Reynolds equation considering the flow factor was solved, and the influence of operating and structural parameters on the lubrication state of the seal face was studied.The results show that, with the increasing of speed, the film thickness and bearing coefficient are gradually in- creased, and the asperity contact force is gradually decreased to zero, which realizes the separation of sealing rings.The me- dium with low viscosity has a significant effect on the critical speed.The critical speed and the closed force are increased linearly with the increasing of the pressure difference. The critical speed is increased with the increasing of groove depth and helix angle, and decreased with the increasing of the number of groove and the ratio of dam and groove width. The groove depth has the most significant influence among structure parameters.It would have better lubrication transit ability with parameters showed in the paper：groove depth 3-7μm,helix angle 14°- 18°,the number of grooves 16-24,ratio of dam width to groove width 2/3 ~ 5/6.