COMPUTATIONAL AND EXPERIMENTAL STUDY OF CONJUGATE HEAT TRANSFER FROM A FLAT PLATE WITH SHOWER HEAD IMPINGING JETS

Computational and experimental conjugate heat transfer of flat circular disk is investigated with a constant heat flux imposed on its bottom surface and a shower head of air jets impinging on its top surface. The shower head consists of a central air jet surrounded by four neighboring perimeter jets. Measured temperature data at twelve locations within the plate are compared with the conjugate heat transfer result obtained at the same locations computationally by Shear Stress Transport (SST) kappa-omega turbulence model. Measurement and simulation results are in good agreement with each other. The spacing to orifice diameter ratio (H/d = 1 to 6), jet Reynolds number (7115 to 10674) and plate thickness (2.5 mm, 10 mm and 20 mm) are varied. The computationally obtained flow structure describes the complex interaction of the wall jets. Heat transfer rate is found to be independent of thickness of the impingement plate. Local variation of heat transfer rate with varying H/d is significant but its effect on the area weighted average heat transfer rate is very small. Shower head jets provide uniform temperature distribution with higher heat transfer rate in comparison with the single jet.