基于二阶滑移边界的螺旋槽干气密封协调优化

应用二阶非线性滑移边界条件推导出修正的广义雷诺方程,并用PH线性化方法、迭代法对非线性雷诺方程近似求解,得到气膜推力和气膜刚度的近似解析式。利用多目标优化方法构建气膜刚度与泄漏量之比的协调函数,对该目标函数进行近似求解,获得最佳的螺旋槽几何参数值。利用Maple程序计算不同介质压力和转速下的气膜刚度、泄漏量并与试验值进行对比。结果表明,几何参数优化的干气密封样机测试结果与理论计算结果误差较小,运用二阶非线性滑移边界条件计算出的理论值具有较好的精度。

Coordination and optimization in spiral groove gas seal based on the second order slip boundary

The modified generalized Reynolds equation was derived under the second order nonlinear slip boundary conditions.The nonlinear Reynolds equation was solved to obtain the approximate solution of gas film thrust by using the PH linearization method and iterative method.Then,the gas film stiffness approximate solution was obtained by derivativing gas film thickness.And a trade-off function of rigidity-to-spillage ratio was derived and the optimized geometric parameters were acquired by solving the objective function.Then the gas film stiffness values and leakage values were calculated under the different media pressure and rotational speed by using Maple program according to an engineering instance,which were compared with the experimental values.The results show that the testing values of dry gas seal prototype under the optimized geometric parameters are closed to the theoretical numerical calculation.The theoretical numerical values calculated by using the second order nonlinear slip boundary conditions have good precision.