螺旋槽干气密封润滑气膜角向涡动的稳定性分析

螺旋槽干气密封操作的稳定性和可靠性与其槽形参数密切相关，优化槽形参数一直是该领域研究的热点。应用PH线性化方法及变分运算干气密封螺旋槽内瞬态微尺度流动场的非线性雷诺方程，得到了气膜角向涡动刚度的解析式。继而利用复数转换和迭代法对稳态下气膜边值问题进行求解，求得了气膜涡动刚度的近似解析解。通过动态稳定性分析，获得了不同介质粘度、压力和转速下稳定性最佳的螺旋角数值。研究结果表明：随介质压力和转速增大，气膜涡动刚度越大，稳定性越好。

A stability analysis for lubricating gaseous film of spiral grooved gas seals subjected to angular eddy motion

The operating stability and reliability in spiral grooved gas seals is closely related to the geometric parameters,and hence optimization of the parameters is an important research area.Using PH linearization and the variation method,a nonlinear Reynolds equation for a transient state and micro-scale flow field was solved,and the approximate function expression of gaseous film rigidity under angular eddy motion was derived.The steady-state boundary value problem for a gaseous film was then solved by using complex functions and a small parameter iterative method,and an approximate solution for the gaseous film rigidity was obtained.The optimum helix angles under different dielectric viscosity,pressure and rotating speed were acquired by analyzing the dynamic stability.The result shows that gaseous film rigidity under angular eddy motion will rise and its stability will increase with increasing pressure and rotation speed.