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

Key words:  spiral groove  dry gas seals  nonlinear slip boundary  Maple program  optimization

Abstract:

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 ilerative 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.