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Experimental Determination of Forced Convection Evaporative Heat Transfer Coefficients for Nonazeotropic Refrigerant Mixtures.


pdf icon Experimental Determination of Forced Convection Evaporative Heat Transfer Coefficients for Nonazeotropic Refrigerant Mixtures. (2775 K)
Radermacher, R.; Ross, H.; Didion, D. A.

ASME 83-WA/HT-54;

Winter Annual Meeting, 1983. American Society of Mechanical Engineers (ASME). November 1983, 1983.

Keywords:

refrigerants; forced convection; heat transfer; mixtures; experiments; conservation; heating; data analysis

Abstract:

A number of experiments were conducted in the 1960's to determine the two phase heat transfer coefficient of pure refrigerants. Recently energy conservation requirements spurred interest in nonazeotropic refrigerant mixtures, because such mixtures can improve theoretically the COP of certain refrigerant cycles. The two phase heat transfer coefficient of such mixtures under forced convection conditions is virtually unknown. An experimental rig has been constructed to investigate where it is possible to predict the heat transfer coefficient of the mixture based on the coefficients of the components. Initially data was taken on R-22 and compared to literature data and to existing predictive correlations. Good agreement was found with the literature's data on forced convection, single phase heat transfer correlations, and some to two phase evaporative correlations. Single phase,heating and two phase boiling experiments were conducted then on R22 and R22 individual and in various mixture concentrations. The results of these tests are reported in the paper.