Abstract:In order to explore the gas-liquid-solid flow characteristics and sealing performance on micro-gap of dynamic pressure mechanical seal, a gas-liquid-solid multiphase flow model of gap lubrication film was established to simulate the gap flow to analyze the effects of channel parameters and operating parameters on the flow characteristics and sealing performance. The results show that the increase of groove width ratio, helix angle and speed, and the decrease of groove depth will increase the cavitation area of the lubrication film. With the increase of groove width ratio, groove ratio and groove depth, the opening force of the lubricating film increases first and then decreases. The optimum groove type parameters are groove width ratio 0.3~0.6, groove diameter ratio 0.7~0.8, groove depth. 6~10μm(high speed and high depth), Smaller helix angle for greater opening force. In the studied parameters, the seal is mainly negative leakage, and the increase of the rotational speed, the ratio of the groove diameter and the decrease of the helix angle will increase the absolute value of the leakage, and the increase of the groove depths and the groove width ratio will increase the absolute value of the lea-kage first and then decrease. In general, the solid particles are mainly concentrated in the tank area and the inner side of the dam area. The decrease of the ratio of the groove diameter and the increase of the helix angle, cause the solid particles to aggregate in the trough area, which easily cause the the spiral groove to be blocked and then failed.
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