Numerical Analysis of Roughened Target Surface for Enhancing Jet Impingement Cooling

Roughening on a surface is crucial in heat transfer, primarily enhanced by the increased interaction between the fluid and the surface. Considering this, a thorough study was conducted to explore impinging jet array cooling (IJAC) applied to a semicircular curved surface, enhanced with aerofoil-shaped fins. Analyses were conducted under different Reynolds numbers (Re), fin arrangements, and nozzle-to-target surface spacings (S/d). Extensive analyses were conducted for both roughened and smooth target surfaces. The roughened surface and extending the nozzles to the surface increased the Nu numbers relative to the conventional IJAC scheme. The obtained heat transfer improvement was about 52.81%. In addition, the heat transfer distribution on the surface has become more homogeneous. The results of the study showed that a roughened target surface with elongated jets has significant potential for internal cooling.