本文利用数值法计算了带有环向波度和径向锥度端面机械密封的流体膜压力分布和膜压系数,结果表明:环向波度的影响大于径向锥度。分析了流体静压与动压效应。并由压力的叠加建立了流体膜承载能力与外加载荷的关系,得到了膜厚计算式。通过对介质介电常数的测试、动态寄生电容的测试和改变动环引线方式,提高了电容法膜厚测量的精度。设计的测试线路可自动连续记录转速与膜厚的关系,直观地反映出流体膜的形成过程和变化情况。 In this paper, the pressure distribution and membrane pressure coefficient of the fluid film with circumferential wave and radial taper end face mechanical seal are calculated by numerical method. The results show that the influence of ring wave direction is larger than that of radial taper. The effects of hydrostatic pressure and dynamic pressure were analyzed. By the superposition of pressure, the relationship between the bearing capacity of fluid film and the applied load was established, and the formula of film thickness was obtained. By measuring the dielectric constant of the medium, testing the dynamic parasitic capacitance and changing the way of the lead of the moving ring, the accuracy of the capacitance film thickness measurement is improved. The designed test circuit can automatically record the relationship between rotation speed and film thickness automatically and directly reflect the formation process and change of the fluid film.