THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

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Experimental studies on improvement of COP of window air conditioning unit

ABSTRACT
This paper presents the performance analysis of a window air conditioner unit incorporated with Wick less Loop Heat Pipes(WLHP).The WLHPs are located on the evaporator side of the air conditioning unit. The working medium for the WLHPs is R134a refrigerant gas, an alternate refrigerant. The supply and return humidity of room air, the heat removal rat and, the COP (Coefficient of Performance) of the unit are analyzed for various ambient and room temperatures before and after incorporation of WLHPs. The performance curves are drawn by comparing the power consumption and humidity collection rates for various room and ambient temperatures. The results show that the COP of the unit is improved by 18% to 20% after incorporation of WLHPs due to pre cooling of return air by WLHPs, which reduces the thermal load on compressor. Similarly the energy consumption is reduced by 20% to 25% due to higher thermostat setting and the humidity collection is improved by 35% due to pre cooling effect of WLHPs. The results are tabulated and conclusion drawn is presented based on the performance.
KEYWORDS
PAPER SUBMITTED: 2014-12-15
PAPER REVISED: 2015-08-08
PAPER ACCEPTED: 2015-08-10
PUBLISHED ONLINE: 2015-09-26
DOI REFERENCE: https://doi.org/10.2298/TSCI141215139T
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