Experimental and Numerical Studies of Heat Transfer Characteristics for Impinging Jet on Dimple Surfaces

Abstract

Experimental and numerical works have been carried out to investigate the effect of impingement dimples surface on heat transfer characteristics in a circular test plate. Impingement jet technique and dimple shape can enhances the heat transfer rate caused by the high turbulence intensity. The cylindrical shape of dimple was used in this work. The simulation results were validated with the experimental data obtained from 4 types test plates. The simulate data displayed the flow structure and contour temperature surface on the test plate which provided the complex flow and heat transfer characteristics. The experimental results showed that the case of the dimple diameter (d) equal to the jet diameter (Dj), and the distance between jet and the test plate (B) is 2 times of Dj, yielded the maximum heat transfer rate. The heat transfer rate enhanced up to 200 % compared to a flat plate at Rej = 14,500.