THERMAL SCIENCE

International Scientific Journal

Raviwat Srisomba

,

Lazarus Godson Asirvatham

,

Omid Mahian

,

Ahmet Selim Dalkılıç

,

Mohamed M. Awad

,

Somchai Wongwises

AIR-SIDE PERFORMANCE OF A MICRO-CHANNEL HEAT EXCHANGER IN WET SURFACE CONDITIONS

ABSTRACT
The effects of operating conditions on the air-side heat transfer, and pressure drop of a micro-channel heat exchanger under wet surface conditions were studied experimentally. The test section was an aluminum micro-channel heat exchanger, consisting of a multi-louvered fin and multi-port mini-channels. Experiments were conducted to study the effects of inlet relative humidity, air frontal velocity, air inlet temperature, and refrigerant temperature on air-side performance. The experimental data were analyzed using the mean enthalpy difference method. The test run was performed at relative air humidities ranging between 45% and 80%; air inlet temperature ranges of 27, 30, and 33°C; refrigerant-saturated temperatures ranging from 18 to 22°C; and Reynolds numbers between 128 and 166. The results show that the inlet relative humidity, air inlet temperature, and the refrigerant temperature had significant effects on heat transfer performance and air-side pressure drop. The heat transfer coefficient and pressure drop for the micro-channel heat exchanger under wet surface conditions are proposed in terms of the Colburn j factor and Fanning f factor.
KEYWORDS
automotive air-conditioning, heat transfer coefficient, micro-channel heat exchanger, pressure drop, R 134a
PAPER SUBMITTED: 2015-09-06
PAPER REVISED: 2016-09-24
PAPER ACCEPTED: 2016-09-06
PUBLISHED ONLINE: 2016-10-01
DOI REFERENCE: https://doi.org/10.2298/TSCI150906227S
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2017, VOLUME 21, ISSUE Issue 1, PAGES [375 - 385]
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Air-side performance of a micro-channel heat exchanger in wet surface conditions

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