气体润滑环瓣式浮动环密封高速特性

Behavior of a Gas Lubricated Split Floating Ring Seal Operating at High speed

基于气体润滑理论,考虑浮动环瓣力平衡与力矩平衡,对气体润滑环瓣式浮动环密封高速特性开展数值分析研究。计算得到密封面压力分布规律,并分析转速、密封压力等操作参数对平衡膜厚、平衡转角、泄漏量、气膜刚度、刚漏比等密封参数的影响规律。结果表明:密封面楔形收敛间隙可以产生显著动压效应,最小膜厚与环瓣偏角随主轴转速增加而增大,但是随密封压力增加而减小;泄漏率随转速与密封压力增加而增大,气膜静态刚度、角向刚度、刚漏比随转速增加而降低,随密封压力增加而增大。

Theoretical analyses with considering force equilibrium and moment equilibrium were carried out to investigate the sealing performance of the split floating ring seal operating at high rotational speed. A mathematical model was presented based on gas lubrication theory.The pressure distribution of gas film was obtained,and the influence of rotation speed and sealing pressure on sealing performance was investigated numerically.Results show that significant hydrodynamic effect is developed because of the convergent gap,the film thickness and deflection angle are increased with the increasing of rotational speed and decreased with the increasing of sealing pressure.The leakage rate is increased with the increasing of the rotational speed and the pressure difference.The gas film static and angle stiffness,and the ratio of stiffness to leakage rate are decreased with the increasing of rotational speed and increased with the increasing of seal pressure.