Heat transfer and flow analysis of jet impingement on concave surfaces

The current study evaluates the performance of three turbulence models in predicting the heat transfer and flow physics of jet impingement on concave surfaces. Two of the applied models are zero equation subgrid-scale (SGS) models which belong to large eddy simulation (LES), namely the RAST and dynamic Smagorinsky model (DSM), and the third one is RNG k-is an element of Reynolds Averaged Navier Stokes (RANS) model. These models are utilized to analyze the heat transfer for two cases: (1) jet impingement on a curved surface with different jet to surface distances (2) jet impingement on a heated circular cylinder with varying nozzle to surface distances at two different Reynolds numbers. The predicted results are compared with the available experimental data in the literature. The findings revealed that RAST and DSM predictions are in better agreement with experiments than RNG k-is an element of model. It is also concluded that at higher jet to surface ratios, all three models produced almost similar results, proving that the heat transfer distribution and the flow are more affected by the jet to surface distance than the magnitude of Reynolds number. (C) 2015 Elsevier Ltd. All rights reserved.