Theoretical Investigation of The Optimal Spray-Condenser Configuration of A Sprayed Finned-Tube Air-Cooled Condenser: Analysis of the Intensification Factor And Water Loss Spots

Theoretical Investigation of The Optimal Spray-Condenser Configuration of A Sprayed Finned-Tube Air-Cooled Condenser: Analysis of the Intensification Factor And Water Loss Spots

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© 2021 by IJETT Journal
Volume-69 Issue-12
Year of Publication : 2021
Authors : Ibra BOP, Biram Dieng, Seydou Nourou DIOP, and Amadou WARORE
DOI :  10.14445/22315381/IJETT-V69I12P204

How to Cite?

Ibra BOP, Biram Dieng, Seydou Nourou DIOP, and Amadou WARORE, "Theoretical Investigation of The Optimal Spray-Condenser Configuration of A Sprayed Finned-Tube Air-Cooled Condenser: Analysis of the Intensification Factor And Water Loss Spots," International Journal of Engineering Trends and Technology, vol. 69, no. 12, pp. 21-29, 2021. Crossref, https://doi.org/10.14445/22315381/IJETT-V69I12P204

Abstract
Spraying water upstream of an air-cooled condenser is an efficient way to improve the energetic performance of a refrigeration system. In this work, the optimal spray-condenser configuration, which allows covering the maximum surface to be cooled while avoiding as much water loss as possible, is investigated. The target area is represented by the front surface of the condenser (Sf = 0,2 X 0, 2 m2). The calculation model, applied to a finned-tube air-cooled condenser, is developed using Matlab software in order to visualize changes in lost water flow rates and the thermal intensification factor. It is found that the best cooling and the minimum water loss are recorded when the spray impact surface is just inscribed on the front surface of the condenser and when the misting regime is without an excess of water. In this configuration, the ratio of the spray impact area to the condenser frontal area is equal to 0,9398. But when the misting regime with an excess of water is reached, water loss through drainage is added to the total lost water flow. On the other hand, when the spray impact area is greater than the front surface of the condenser, only a portion of the water flow enters the condenser, and the intensification factor decreases. The results also show that the outer wall temperature from which one works in the misting regime without an excess of water depends strongly on the collected water flowrate (Twall > 30 °C for 0, 0231 mg.s-1 and Twall > 40 °C for 0,0462 mg.s-1).

Keywords
Optimal configuration, air-cooled condenser, thermal intensification factor, frontal area, spray and water flow rate

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