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Performance of HC and HFC Refrigerants in a Finned-Tube Evaporator and Its Effect on System Efficiency.


pdf icon Performance of HC and HFC Refrigerants in a Finned-Tube Evaporator and Its Effect on System Efficiency. (103 K)
Domanski, P. A.; Yashar, D. A.; Kim, M. S.

Natural Working Fluids Conference, 6th IIR Gustave Lorentzen. Proceedings. August 29-September 1, 2004, Glasgow, UK, 1-8 pp, 2004.

International Journal of Refrigeration, Vol. 28, No. 6, 820-827, September 2005.

Keywords:

refrigerants; tubes; efficiency; evaporator

Abstract:

The paper presents a comparable evaluation of isobutane (R600a), propane (R290), R134a, R22, R410A, and R32 in an optimized finned-tube evaporator, and analyzes the impact of evaporator effects on the system coefficient of performance (COP). The study relied on a detailed evaporator model derived from NIST's EVAP-COND simulation package and used the ISHED1 scheme employing a non-Darwinian Learnable Evolution Model for circuitry optimization. In the process, 4500 circuitry designs were generated and evaluated for each refrigerant. The obtained evaporator optimization results were incorporated in a conventional analysis of the vapor compression cycle. For a theoretical cycle analysis without accounting for evaporator effects, the COP spread for the studied refrigerants was as high as 11.7%. For cycle simulations including evaporator effects, the COP of R290 was better than that of R22 by up to 3.5%, while the remaining refrigerants performed within approximately a 2% COP band of the R22 baseline for the two condensing temperatures considered.