Comparing Single Phase Heat Transfer to Arrays of Impinging Jets and Sprays

The single phase heat transfer characteristics of square arrays of impinging water sprays were investigated experimentally. A total of 230 experimental points, covering a wide range of flow rates and different spray array geometries were obtained with three different models of commercially available full cone spray nozzles. Results were compared to an available correlation for the area average heat transfer coefficient of impinging arrays of submerged jets. It is shown that spray impingement techniques may provide the same heat transfer coefficient obtained with impinging jets under much smaller coolant flow rates per unit heated area. Coolant pumping power required by both techniques was also compared. It is shown that spray arrays require, for the establishment of a given area average heat transfer coefficient, more pumping power than submerged jet arrays.Copyright © 2002 by ASME