阶梯收敛槽机械密封空化效应及密封性能优化分析

为解决波度端面机械密封精密加工困难的问题，基于收敛型槽具有较低的泄漏量和较高的流体静压效应的特点，提出一种由波度端面机械密封结构衍生变化的阶梯收敛槽机械密封结构，考虑空化作用，对不同结构参数及工况参数下机械密封密封性能进行CFD流体仿真分析。结果表明：工况参数及结构参数对液膜空化效应有显著的影响，其中随着膜厚、密封压力以及槽深的增加，液膜空化效应均减弱，随着转速的增大，液膜空化效应变强。以开漏比评价密封性能，结果表明，阶梯收敛槽机械密封在小膜厚、高转速、较低密封压力以及较小静环开槽深度下运行时可获得最优密封性能；但为保证密封端面液膜具有足够的承载力，开槽深度不宜过小。

Cavitation Effect and Sealing Performance Optimization Analysis of Stepped Convergent Groove Mechanical Seal

In order to solve the problem of precision machining of wavy end face mechanical seal,based on the characteristics of convergent grooves with lower leakage and higher hydrostatic pressure effect,a stepped convergent groove mechanical seal structure derived from the wavy end face mechanical seal structure was proposed.Considering the cavitation effect,CFD fluid simulation analysis was carried out for the sealing performance of the mechanical seal under different structural parameters and working conditions.The results show that the operating conditions and structural parameters have a significant effect on the cavitation effect of liquid film.As the film thickness,the sealing pressure and the groove depth increase,the cavitation effect of liquid film decreases,and as the rotating speed increases,the cavitation effect increases.The evaluation of sealing performance based on the open leakage ratio shows that the stepped convergence groove mechanical seal can achieve optimal sealing performance when operating at small film thickness,high speed,lower sealing pressure,and smaller depth of static ring groove.However,to ensure that the liquid film on the sealing end face has sufficient bearing capacity,the groove depth should not be too small.