Advanced Modelling of Flow and Heat Transfer in Rotating Disc Cavities Using Open-Source CFD

Abstract

Code_Saturne, an open-source computational fluid dynamics (CFD) code, has been applied to a range of problems related to turbomachinery internal air systems. These include a closed rotor-stator disc cavity, a co-rotating disc cavity with radial outflow and a co-rotating disc cavity with axial throughflow. Unsteady Reynolds-averaged Navier-Stokes (RANS) simulations and large eddy simulations (LES) are compared with experimental data and previous direct numerical simulation (DNS) and LES results. The results demonstrate Code_Saturne’s capabilities for predicting flow and heat transfer inside rotating disc cavities. The Boussinesq approximation was implemented into the code for modelling centrifugally buoyant flow and heat transfer in the rotating cavity with axial throughflow. This is validated using recent experimental data and CFD results. Good agreement is found between LES and RANS modelling in some cases, but for the axial throughflow cases, advantages of LES compared to URANS are significant for a high Reynolds number condition. The wall-modelled large eddy simulation (WMLES) method is recommended for balancing computational accuracy and cost in engineering applications.