Heat transfer characteristics of free surface water jet impingement on a curved surface

Impinging jet studies are available in the literature, which involves air as a working fluid or water in the submerged jet configuration. However, literature is scarce for free surface liquid jet impingement. In this work, heat transfer characteristics of free surface water jet impingement on a convex uniformly heated semi-cylindrical curved surface is presented. In experiments, two different curvature ratios, Did are considered, where d is the inner diameter of circular nozzle pipe, and D is the outer diameter of the semi-cylindrical convex surface. Jet to surface distance was fixed to H/d = 4 (d = 6 mm). Reynolds number ranging from 17036 to 42590 were considered for experimental study. Nusselt number contours are presented for three different Reynolds numbers and two different curvature ratios, in which one case was D/d = infinity (flat surface). Present investigation revealed that surface curvature effects heat removal rate near the stagnation point. Heat transfer away from the impact in the circumferential direction is found to be affected by curvature, especially for higher Reynolds number (Re = 42590). (C) 2020 Elsevier Ltd. All rights reserved.