Research On The Face Structure And Flow Field Of Waviness Mechanical Seal

Waviness mechanical seal is mainly used in shaft seal of nuclear power plant primary coolant pump. As products of nuclear main pump mainly rely on import, it is hard to find the studies about nuclear main pump seal in our country, and research on nuclear main shaft seal sealing performance has important practical significance.Face structure and flow field of waviness mechanical seal is analyzed in this paper. According to the actual parameters of the nuclear main pump spindle, set up mathematical model, use finite difference method to discrete Reynolds Equation, write a program to get pressure value of each node in Matlab software; according to the pressure distribution, get parameters, such as the opening force, stiffness, leakage, stiffness-leakage rate. By changing the structure and operating parameters, analyze the influence of changes in their sealing performance. Specific conclusions are as follows:(1)With film thickness increasing, seal opening force, stiffness and stiffness-leakage rate decreases, while the leakage rate increases significantly with film thickness increasing.(2)With the increase of the amplitude, the opening force and leakage increases. Stiffness increases at the beginning to the maximum 2.5μm, then decreases with the amplitude increasing. Stiffness-leakage rate achieves maximum when amplitude at 1.5μm(3)Opening force and leakage increase with wave number increasing, but the increase is not significant. Stiffness achieves maximum when wave number at 19. Stiffness-leakage rate achieves maximum when wave number at 16.(4)With breadth rate of dam zone increasing, Opening force and stiffness decreases, leakage is reduced. Stiffness-leakage rate changes a little from 0.2 to 0.4, achieves the maximum when breadth rate of dam zone at 0.3.(5)With speed increasing, opening force, stiffness and stiffness-leakage rate increase significantly, leakage also slightly increases but it is not obvious.