Heat Transfer on a Film Cooled Inlet Guide Vane

The steady flow and temperature fields around a film cooled inlet guide vane are determined numerically by a CFD method. In particular the outer surface temperatures and heat transfer coefficient distributions are calculated. Static pressure distributions are also presented. The film cooling is achieved by 10 rows of film cooling holes. The computed results are compared with experimental data. The governing equations are solved by a 3D finite-volume Navier-Stokes solver. The low Reynolds number version of the k-ω turbulence model by Wilcox is implemented to enable calculations of turbulent flow cases. A realizability constraint is applied to reduce the generation of unphysical turbulent kinetic energy, particularly close to the leading edge. To handle the film cooling process a special procedure is used. An injection model was implemented in the computer code. This injection model adds the mass flow rate passing through the film cooling holes to the main flow as source terms in the equations for mass, momentum, energy and turbulent kinetic energy. The grid used in the calculations is block-structured, and the total number of grid points is around 250,000. In a related investigation for the same vane geometry but considering pure convective heat transfer, the authors have investigated the importance of the wall thermal boundary condition. Based on this a conjugate heat transfer approach was applied in this paper. The conjugate heat transfer condition means that the heat transfer coefficient distribution is prescribed on the inner surface of the vane and also the wall thickness and thermal conductivity of the vane material are prescribed. The vane outer surface temperature is then found as part of the numerical solution. Some essential parameters in the injection model were varied and the calculated results for the vane outer surface temperature were found to compare favourably with measurements. The static pressure distribution on the vane surface agrees well with experiments. The Mach number distribution provides information of the flow field.