Enhancing the Heat Transfer Rate Through Surface Manipulation

Abstract

In the present paper, the flow characteristics and the heat transfer rate of turbulent dual jet impinging on a sinusoidal wavy surface are numerically studied. Finite-volume-based two-dimensional Reynolds-averaged Navier–Stokes equations are used to handle the complex behavior of the turbulent dual. The offset ratio is varied from 3 to 15 with an interval of 2. To evaluate the role of sinusoidal wavy surface on flow and heat transfer characteristics, the amplitude and number of cycle are varied from 0.1 to 0.7 m and from 4 to 12 with an interval of 0.1 m and 1, respectively. In the present numerical work, the Reynolds number and Prandtl number are set to 15,000 and 0.71, respectively. The bottom wall is maintained at a constant temperature. The results show that the sinusoidal wavy surface affects both the flow characteristics and heat transfer rate, and that it also enhances the heat transfer rate significantly. Approximately, a maximum of 23.27% enhancement in heat transfer rate is achieved with respect to the plane wall surface. It is also found that the average Nusselt number depends on both amplitude and number of cycle of the sinusoidal wavy surface.