There are many questions surrounding the transition to low global warming potential (GWP) refrigerants, including the performance of these refrigerants in existing and new refrigeration systems and heat pumps. This paper identifies studies which measured evaporation andor condensation heat transfer coefficients for low GWP alternatives to R410A such as R32 and R452B. Several papers studied R32, but the data on R452B was very limited. Subsequently, heat transfer coefficients were predicted for evaporation and condensation of R32 and R452B and compared to R410A. The Shah (2009) and Kim and Mudawar (2013) correlations were used to predict condensation, while the Kandlikar (1990), Klimenko (1988), and Takamatsu et al. (1993) correlations predicted evaporation. Since low charge systems are preferable to mitigate flammability risk from A2L refrigerants, correlations were applied to small diameter tubes [i.e., 1-5 mm (0.039-0.20 in)] over a range of qualities and mass fluxes [i.e., 75-400 kg/m²s (15-82 lbm/ft²s)]. The correlations agreed with previous data. In general, predicted R32 evaporation and condensation heat transfer coefficients were higher than R410A, whereas heat transfer in R452B was similar to or slightly higher than R410A.
Citation: 2017 Annual Conference, Long Beach, CA, Conference Papers
Product Details
- Published:
- 2017
- Number of Pages:
- 8
- Units of Measure:
- Dual
- File Size:
- 1 file , 1.1 MB
- Product Code(s):
- D-LB-17-C048
