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Horizontal Flow Boiling of Alternative Refrigerants Within a Fluid Heated Micro-Fin Tube.



M P. Kaul, Mark A. Kedzierski, David Didion


This paper presents local, fluid-heated, flow boiling measurements for three refrigerant mixtures: [1] R410B (R32/125, 45/55 % mass), [2] R32R134a (28/72 % mass) and [3] R407C (R32/125/134a, 25/23/52 % mass). Flow boiling heat transfer coefficients for the mixtures pure components and R22 were also measured to establish a baseline for the heat transfer degradation calculations. The heat transfer degradation was shown to be a relatively strong function of heat flux and thermodynamic mass quality. The heat transfer degradation associated with the R32/125 mixture was believed to be mostly due to nonlinear property effects. The R410B appears to be a good alternative refrigerant for R22 having approximately a 20% larger heat transfer coefficient. The degradation of the R407C was shown to increase with heat flux for all qualities except for 0.6. The dependency of the R32/134a degradation was not consistent with heat flux. The influence of nonlinear property effects was apparently responsible for the inconsistency. Correlations of the two-phase Nusselt number were derived for each fluid.
Proceedings Title
Georgia Institute of Technology
Conference Dates
November 16, 1996
Conference Location
New York, NY, US
Conference Title
Process, Enhanced, and Multiphase Heat Transfer


refrigerants, enhanced heat transfer, fluid heating, microfin, refrigerant mixtures


Kaul, M. , Kedzierski, M. and Didion, D. (1996), Horizontal Flow Boiling of Alternative Refrigerants Within a Fluid Heated Micro-Fin Tube., Georgia Institute of Technology, New York, NY, US, [online], (Accessed April 15, 2024)
Created November 15, 1996, Updated October 12, 2021