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-∈ 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-∈ 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.