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Fundamental Aspects of the Application of Carbon Dioxide in Comfort Cooling.


pdf icon Fundamental Aspects of the Application of Carbon Dioxide in Comfort Cooling. (187 K)
Brown, J. S.; Domanski, P. A.

ICR0100;

Refrigeration International Congress, 21st IIR. (IRC2003).Technical Session: B1-9 - A New Old Refrigerant: Carbon Dioxide - Components and Systems I. Proceedings. August 17-22, 2003, Washington, DC, 2004.

Keywords:

carbon dioxide; comfort; cooling; refrigerants; refrigeration; evaporators; entropy

Abstract:

This paper presents entropy generation analyses for the evaporator, compressor, gas cooler, expansion device and liquid-line suction-line heat exchanger for a transcritical carbon dioxide cycle for automotive and residential air-conditioning systems, and presents entropy generation analyses for the evaporator, compressor, condenser, and expansion device for a subcritical R134a automotive air-conditioning system and a subcritical R22 residential air-conditioning system. The analyses show that the CO2 automotive air-conditioning system generates 36% more entropy than the R134a automotive air-conditioning system, and that the CO2 residential air-conditioning system generates 63% more entropy than the R22 residential air-conditioning system. The biggest contributors to the lower CO2 performance are the heat rejection process and the expansion related processes.