Application of Computational Fluid Dynamics to Turbine Disk Cavities

Abstract

A CFD code for the prediction of flow and heat transfer in rotating turbine disk cavities is described and its capabilities demonstrated through comparison with available experimental data. Application of the method to configurations typically found in aeroengine gas turbines is illustrated and discussed. The code employs boundary-fitted coordinates and uses the k–ε turbulence model with alternative near-wall treatments. The wall function approach and a one-equation near-wall model are compared and it is shown that there are particular limitations in the use of wall functions at low rotational Reynolds number. Validation of the code includes comparison with earlier CFD calculations and measurements of heat transfer, disk moment, and fluid velocities. It is concluded that, for this application CFD is a valuable design tool capable of predicting the flow at engine operating conditions, thereby offering the potential for reduced engine testing through enhanced understanding of the physical processes.