BFRL ICON 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.



Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899