THERMAL SCIENCE

International Scientific Journal

Jahar Sarkar

,

Souvik Bhattacharyya

,

Mudali Ramgopal

EXPERIMENTAL INVESTIGATION OF TRANSCRITICAL CO2 HEAT PUMP FOR SIMULTANEOUS WATER COOLING AND HEATING

ABSTRACT
This paper presents the experimental performances of a transcritical CO2 heat pump prototype for simultaneous water cooling and heating applications. System behavior and performances such as cooling capacity, heating capacity, and system coefficient of performance (COP) have been studied experimentally for various operating parameters such as water mass flow rate, water inlet temperature for both evaporator and gas cooler, and expansion valve opening. Performance is also compared with previous test data. Test indicates that the expansion valve opening has a significant effect as well near the full valve closing condition (up to 20°). Study shows that both the water mass flow rate and inlet temperature have significant effect on system performances. Test results show that, at gas cooler pressure of 90 bar, the effect of evaporator water mass flow rate on the system performances is more pronounced (COP increases 0.6 for 1 kg/min.) compared to the gas cooler water mass flow rate (COP increases 0.4 for 1 kg/min.) and the effect of gas cooler water inlet temperature is more significant (COP decreases 0.48 for given ranges) compared to the evaporator water inlet temperature (COP increases 0.43 for given ranges).
KEYWORDS
CO2 heat pump, transcritical, gas cooler, water cooling and heating, valve opening
PAPER SUBMITTED: 2008-08-22
PAPER REVISED: 2009-07-13
PAPER ACCEPTED: 2009-08-03
DOI REFERENCE: https://doi.org/10.2298/TSCI1001057S
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2010, VOLUME 14, ISSUE Issue 1, PAGES [57 - 64]
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Experimental investigation of transcritical CO2 heat pump for simultaneous water cooling and heating

© 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