The Numerical Simulation and Research of the Flow Field and Leakage of the Labyrinth Seals

The three-dimensional flow flied model of labyrinth seals was solved to obtained the leakage of the flow with the standard k-e turbulence model,utilizing a general Computational Fluid Dynamics(CFD) program Fluent,and the characteristics of the flow flied with the whirling rotor was studied in different situation,such as eccentrics and pressure ratios.In the paper,the effects of the whirling speed,outlet/inlet pressure ratio and eccentric displacement on the leakage of the labyrinth seal were analyzed.It was found that when the whirling speed was improving,the leakage was decreasing.And the different pressure ratios made the different axial speeds of the flow.When the speed was transonic or faster,the leakage reached the maximum.In addition,the bigger radial displacement of the eccentric caused the higher leakage of the seal.Base on the CFD results,the Egli's empirical formula of the leakage on the labyrinth seals was modification and improvement.And the new empirical formula is useful to calculate the leakage with the labyrinth seal designing or rotating machinery operation.