COOLING EFFECTIVENESS OF MIST PRECOOLER FOR IMPROVING ENERGY PERFORMANCE OF AIR-COOLED CHILLER

Main Article Content

Fu Wing YU Kwok Tai YANG Jia YANG Rachel Kam Yung SIT

Abstract

Mist is increasingly applied to precool outdoor air in heat rejection. This study investigates how the coefficient of performance (COP) of an air-cooled chiller varies with a mist precooler at different levels of cooling effectiveness. A multivariate regression model was developed to simulate the operating variables of an air-cooled chiller with mist precooling. The model was validated with typical performance data of an air-cooled centrifugal chiller. The COP would increase by up to 30%, depending on the cooling effectiveness and the wet bulb depression— the difference between the dry bulb and wet bulb temperatures of outdoor air. At a large wet bulb depression, the percentage increase of COP tended to correlate linearly with the chiller capacity. Yet at a small wet bulb depression, the dynamic control of condensing temperature resulted in a non-linear relationship between the percentage change of COP and the cooling effectiveness. Further experimental work is required to optimize cooling effectiveness for the maximum COP. Keywords: air-cooled chiller; coefficient of performance; mist precooling

Article Details

How to Cite
YU, Fu Wing et al. COOLING EFFECTIVENESS OF MIST PRECOOLER FOR IMPROVING ENERGY PERFORMANCE OF AIR-COOLED CHILLER. Thermal Science, [S.l.], mar. 2017. ISSN 2334-7163. Available at: <http://thermal-science.tech/journal/index.php/thsci/article/view/2233>. Date accessed: 21 july 2017. doi: https://doi.org/10.2298/TSCI151112071Y.
Section
Articles
Received 2017-03-06
Accepted 2017-03-13
Published 2017-03-13

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