OPTIMIZATION OF THE SPRAY COOLING PARAMETERS FOR A HEAT SINK BY THE TAGUCHI METHOD

Spray cooling is among the most important technologies available for the removal of energy with high heat capacity. Spray cooling has many geometrical and operational variable parameters. Therefore, the predictive capabilities are quite limited and the exact mathematical expression is very difficult. For this reason, there is a need for experimental studies using statistical methods. In this study, the spray cooling parameters with a hexagonal finned heat sink were investigated in the nonboiling regime. Experiments were performed at a constant surface temperature. The effects of the nozzle-to-heat-sink distance, the widths and heights of the fins, the distance between fins in the x and y directions, air-water flow rates, and spraying time on the heat transfer have been investigated by the Taguchi experimental design method. As a performance characteristic, the Nusselt number has been regarded and the L-18 (2(1) x 3(7)) orthogonal array chosen as an experimental layout for the eight parameters. The optimized results have been found to be a nozzle-surface distance of 400 mm, fin height of 10 mm, fin width of 36 mm, distance between fins of 15 mm in the x direction and 10 mm in the y direction, an air flow rate of 3.6 m(3)/h, water flow rate of 0.03 m(3)/h, and a spraying time of 5 s. The impact of ranking parameters on spray cooling heat transfer was examined. The most effective parameter was found to be spraying time.