Experimental and 3D computational fluid dynamics (CFD) investigation of multiple arrays of jet impingement on a flat surface

This study investigated experimentally and numerically heat transfer of air jet impingement by comparing the surfaced averaged Nusselt number for several turbulence models and gap spacings. A plate with a constant temperature of 60 degrees C was fixed at 30.30 mm and 50.64 mm spacing from vertical jets. Air was pressurized out of orifices to create jets of air with flow open area percentages of 1%, 2% and 3% relative to area of the test plate. The numerical analysis was performed on three grids using the fitting method to produce grid independent solutions. Three turbulence models were employed in the numerical analysis, namely Transition SST, Transition SAS, and DES Transition SST models. The predicted and the measured average Nusselt numbers on the test plate were compared and high accuracy agreement between experimental and numerical results was observed with a maximum deviation of 7.85%. DES Transition SST model was found to be relatively reliable in predicting jet impingement heat transfer with a maximum deviation of 4.55% as compared to the data produced experimentally. The findings of this paper are critical for accurate prediction and optimization of heat transfer for jet impingement problems with the proper turbulence model and numerical methods.