Experimental and numerical study of inclined free surface liquid jet impingement

Abstract

Experimental and computational investigation is carried out to study heat transfer characteristics and to explain the underlying physics for the case of inclined free surface liquid jet impinging on a uniformly heated flat plate. Experimentally, four Reynolds number 17541, 26,311, 35,081, and 438,521 were considered while in the numerical study, Reynolds number of 17,541 and 26,311 were considered. In all the experiments, jet to surface spacing was fixed (H/d=4) and inclination angles of 45o, 30o, 30o and 0o (orthogonal jet) were considered. Local Nusselt number contours are presented for the above range of Reynolds number and inclination angle. Also, profiles of Nusselt number are analyzed and compared for different Reynolds numbers and inclination angles (θ). The numerical study was performed using SST-SAS model and VOF method was used to capture the liquid-air interface. The aim of the numerical study is to explain the underlying physics of heat transfer characteristics through flow dynamics. Streamlines, pressure, velocity, and turbulence intensity are calculated and plotted for a few cases. It is observed that with increasing inclination angle, the location of peak Nusselt number is shifted towards the compression side or uphill side, while the magnitude remains nearly the same. The point of maximum Nusselt number was found to be independent of Reynolds number.