Physical interpretation of flow and heat transfer in preswirl systems

This paper compares heat transfer measurements from a preswirl rotor-stator experiment with three-dimensional (3D) steady-state results from a commercial computational fluid dynamics (CFD) code. The measured distribution of Nusselt number on the rotor surface was obtained from a scaled model of a gas turbine rotor-stator system, where the flow structure is representative of that found in an engine. Computations were carried out using a coupled multigrid Reynolds-averaged Navier-Stokes (RANS) solver with a high Reynolds number k-epsilon/k-omega turbulence model. Previous work has identified three parameters governing heat transfer: rotational Reynolds number (Re-phi), preswirl ratio(beta(p)) and the turbulent flow parameter (lambda(T)). For this study rotational Reynolds numbers are in the range 0.8 * 10(6)