THERMAL SCIENCE

International Scientific Journal

Fu Wing Yu

,

Kwok Tai Chan

,

Jia Yang

,

Rachel Kam Yung Sit

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

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
PAPER SUBMITTED: 2015-11-12
PAPER REVISED: 2016-03-06
PAPER ACCEPTED: 2016-03-09
PUBLISHED ONLINE: 2016-04-09
DOI REFERENCE: https://doi.org/10.2298/TSCI151112071Y
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2018, VOLUME 22, ISSUE Issue 1, PAGES [193 - 204]
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Cooling effectiveness of mist precooler for improving energy performance of air-cooled chiller

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence