Journal of Water and Wastewater; Ab va Fazilab (in persian)

Journal of Water and Wastewater; Ab va Fazilab (in persian)

Applying Dynamic Air Cooling System to Reduce Water Consumption of Iranian-Made Evaporative Coolers

Articles in Press

Document Type : Technical Note

Author
Behzad Omidi Kashani
Assist. Prof. of Mechanical Engineering, Dept. of Mechanical Engineering, Faculty of Engineering, University of Birjand, South Khorasan, Iran
10.22093/wwj.2025.499350.3459
Abstract
The considerable water consumption of Iranian-produced evaporative coolers is obvious to everyone due to the water shortage and the reduction of water resources in Iran. Since Iranian-produced evaporative coolers have an old design and, on the one hand, are well adapted to the atmospheric conditions of Iran, which are mainly hot and semi-arid, but on the other hand, due to the high water consumption in these coolers and the lack of water resources, especially in summer, there is a need to conduct more scientific research and use new ideas and techniques to reduce water consumption in these devices. In this study, a new dynamic air cooling system is first introduced, by which atmospheric air can be cooled to -90oC without using today's conventional refrigeration systems. The dynamic air cooling system is a completely new and innovative method at the global level, which, based on the scientific principles of gas dynamics and thermodynamics, is able to increase the speed of air passing through this system to supersonic values in several stages and, consequently, significantly reduce the temperature of the air passing through the system or its sensible energy. This innovative system is currently being used commercially in industrial cold stores. In the current work, by using the cold air produced by this system, the temperature of the circulating water in evaporative water coolers is significantly reduced, and consequently, the amount of water consumption in evaporative water coolers is reduced. In the current work, it is shown that by using the cold air produced by the dynamic cooling system, the temperature of the circulating water is reduced from the wet bulb temperature of the ambient air to a temperature of 4 oC and in these conditions, the cooling load and the seasonal energy efficiency ratio increase by 97 and 29.2%, respectively, and the water consumption rate and specific water consumption decrease by 35.2 and 67.5%, respectively. Therefore, by using this system in evaporative water coolers produced in Iran, the water and energy consumption rates are both significantly reduced.
Keywords
Evaporative Water Cooler
Dynamic Air Cooling
Water Consumption Reduction
Efficiency Increase
Temperature of Water Circulation
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Journal of Water and Wastewater; Ab va Fazilab (in persian)

Articles in Press, Accepted Manuscript
Available Online from 20 October 2025