Transient Simulation for the Gas Ingestion Through Turbine’s Rim Seal

As the turbine front temperature of the modern aero-engine gets higher and higher, the problem of gas ingestion and the related rim sealing is becoming more and more serious. In this paper, the unsteady numerical simulation of the rim seal model with cavity is carried out, based on the gas ingestion experiment rig of Bath University. Firstly, the CFD results is compared with the experiments to valid the accuracy. The comparison for the pressure distribution shows that the simulation agrees well with the experiments. But the results for the sealing efficiency have some relatively errors. Secondly, the change process for some parameters about the ingestion is discussed. The simulation shows the pressure distribution of main flow is the decisive factor, and the interaction between the blades and the vanes affects the pressure distribution. Thirdly, the effect of the interaction between blade and vanes is provided a close analysis. Interestingly, the periodicity of the sealing efficiency is not consistent with that of the rotating blades. Also, the effect of the axial spacing is obtained through reducing the spacing by twenty percent. The decrease of axial spacing between vane and blade will cause the increase of the peak value of the pressure in the high pressure region.