Variations of Air and Water Temperatures Across and Along the Pads of Direct Evaporative Coolers and Their Effect on the Performance

International Journal of Thermal Engineering

© 2016 by SSRG - IJTE Journal

Volume 2 Issue 3

Year of Publication : 2016

Authors : M. Mosa, A. Saleh

10.14445/23950250/IJTE-V2I6P101

How to Cite?

M. Mosa, A. Saleh, "Variations of Air and Water Temperatures Across and Along the Pads of Direct Evaporative Coolers and Their Effect on the Performance," SSRG International Journal of Thermal Engineering, vol. 2,  no. 3, pp. 1-8, 2016. Crossref, https://doi.org/10.14445/23950250/IJTE-V2I6P101

Abstract:

This paper presents the effect of variations of air and water temperatures across and along the pads of direct evaporative coolers and their effect on the performance. Two thicknesses of a (60cm × 76cm) pad are considered in this study. It is found that, for the thickness of 10 cm, variation of air temperature across the pad varies from 3.7 degrees at the top to 7.4 degrees at the bottom of the pad. For the thickness of 15 cm, variation of air temperature across the pad varies from 6.3 degrees at the top to 10.57 degrees at the bottom of the pad. It was found, also, that the profiles of the air temperature at the lower sectors of the pad are almost identical. The variation of water temperature across the pad was insignificant in the two cases considered. These results are used in optimization of the dimensions of the pad that maximize the performance of the cooler. The optimal thickness is restricted by the acceptable upper limit of relative humidity. It was found that with 70% relative humidity, the optimal thickness was 15 cm while with 85% relative humidity, the optimal thickness was 25 cm.

Keywords:

 direct evaporative cooler, cooler pad, heat and mass transfer, cooling efficiency.

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