School of Engineering, The University of Queensland
Abstract
The objective of this study is to compare the performance of the v 2 -f and the Reynolds Stress Model (RSM) turbulence model with a two-layer wall treatment for the prediction of the mean velocity field, the turbulence characteristics and the heat transfer rate of the normal impinging jet and also impinging jet in a cross-flow configuration. The numerical predictions are validated against detailed experimental measurements, using PIV and a low-wavelength infrared imaging system, for the measurement of turbulent flow features and surface temperatures. A linear pressure-strain model is used in the RSM. The turbulent heat fluxes are modeled by the eddy-diffusivity hypothesis with a constant value of the turbulent Prandtl number. The mesh is refined enough near the solid walls (y+≈1) to adequately resolve the boundary layers. The results show several complex flow-related phenomena that affect the cooling performance, such as stagnation point, separation region, curvature effects and re-circulating wake flows. These phenomena have to be accurately captured before a good prediction of the heat transfer rate can be attained. A comparison between the v 2 -f and RSM results in the stagnation region, in the other near-wall regions and in the free shear region will be presented in order to evaluate the performance of the two models
