Evaporative cooler is the simple, inexpensive way of cooling in the hot and dry countries where conventional air conditioning is not affordable. In the evaporative cooler, heat and mass transfer between the water and air reduces the dry bulb temperature and increases moisture content. In indirect evaporative cooling, primary air cools without coming in contact with the secondary fluid. In the experimental work, thin M.S. sheets are arranged in such a way that it forms wet compartment and dry compartment with the opening’s perpendicular to each other. Holes are drilled on the heat exchanger plate in a specific pattern to increase the cooling effect. In the project, intention is to cool the ambient air to its dew point temperature by providing multiple primary and secondary stages. In the experimental setup manufactured, one side of the heat transfer plate is dry and watertight while the other side of the heat transfer plate has a porous capillary surface. Primary air is cooled without directly coming in contact with the water due to conversion of sensible heat into latent heat. The main objective is to make a cost-effective indirect evaporative cooler without any change in the humidity ratio. Experiments are conducted for different ambient conditions and found that dry bulb temperature decreases by 4 to 5°C while wet bulb temperature decreases by 2 to 3°C without affecting humidity ratio.

evaporative cooling, primary air, dry bulb temperature, wet bulb temperature.

Received: July 11, 2021; Revised: August 4, 2021; Accepted: August 21, 2021; Published: September 24, 2021

How to cite this article: V. W. Bhatkar, Experimental study of multistage indirect evaporative coolers, JP Journal of Heat and Mass Transfer 24(1) (2021), 69-77. DOI: 10.17654/HM024010069

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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