Title: Effects of further cooling the gas cooler outlet refrigerant by an absorption chiller, on a transcritical CO2-compression refrigeration system

Authors: Maryam Salajeghe; Mehran Ameri

Addresses: Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, 7631133131, Iran ' Faculty of Engineering, Department of Mechanical Engineering, Shahid Bahonar University of Kerman, Kerman 7618868366, Iran

Abstract: In this paper, a comparative study is performed for an integrated refrigeration system, based on the first and second laws of thermodynamics. The presented integrated refrigeration system consists of a compression chiller and an absorption chiller powered by a solid oxide fuel cell (SOFC) to generate cooling at low temperatures. The compression chiller employs transcritical CO2 as a refrigerant while LiBr-H2O is used as fluid pair in the absorption chiller. The waste heat from the SOFC operates the absorption chiller, which provides additional cooling. This additional cooling capacity is used to cool down the CO2 exiting the gas cooler of the refrigeration system. Cooling the gas cooler outlet refrigerant reduces the optimum discharge pressure value and improves the energy utilisation factor (EUF). The results reveal that the energy consumption in the integrated refrigeration cycle is lower than that of conventional vapour compression refrigeration cycles.

Keywords: integrated refrigeration systems; LiBr; lithium bromide; H2O; water; transcritical CO2; carbon dioxide; SOFC; solid oxide fuel cells; gas cooler outlet refrigerant; absorption chillers; thermodynamics; compression chillers; waste heat; cooling capacity; energy consumption; refrigeration cycle.

DOI: 10.1504/IJEX.2016.078516

International Journal of Exergy, 2016 Vol.21 No.1, pp.110 - 125

Received: 02 Jul 2015
Accepted: 16 Jan 2016

Published online: 17 Aug 2016 *

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