Heat transfer characteristics under a single turbulent confined slot jet were determined experimentally. New enhancement techniques for the impingement heat transfer rate are proposed and tested experimentally. The results from each enhancement technique are compared with those for a smooth slot nozzle configuration with the same apparatus.;The impingement heat transfer rate was observed to increase due to internal finning of the slot nozzles. Both rectangular and triangular fins were tested. The fins acted as roughness elements. Experimental results with the "rough" nozzle show that the stagnation and average heat transfer rates can be enhanced by up to 15% and 10%, respectively. However, an increase in pressure drop across the nozzles is also noted.;Use of inclined confinement surfaces of 10° and 20° angles accelerate the exit flow provides average impingement heat transfer rates comparable with those for parallel wall confinement. Experimental results show no significant change in the heat transfer distribution for the inclination angle of 10°, while the average heat transfer coefficient is in fact decreased slightly for the inclination angle of 20° at high jet Reynolds numbers.;It was found that insertion of a single turbulence generator in the jet flow provides superior impingement heat transfer without any increase in the system pressure drop. Two types of turbulence generators (square rod and thin plate) were investigated. Both turbulence generators provide the same level of average heat transfer enhancement (up to 15%).
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