The ternary mixture R447A is an ideal substitute of R410A due to its low global warming potential (GWP) and similar physical properties with R410A. In this paper, the flow-boiling heat transfer characteristics of R447A and R410A in a horizontal smooth tube with external diameter of 5 mm was investigated. The experimental conditions are as follows: heat flux of 5-15 kW/m 2, mass flow rate of 100-300 kg/(m 2.s), and evaporation temperature of 5-25 °C. The main research results are as follows: The heat transfer coefficient of R447A ranges from 1000 to 5000W/(m 2·K). The heat transfer coefficient of R447A demonstrates a progressive enhancement with increasing heat flux and mass flow rate. The heat transfer coefficient of R410A exceeds that of R447A by 15% to 28%, with heat flux exerting a more pronounced influence on R410A. Nucleate boiling predominates in the heat transfer process of R410A compared to R447A, while the mass flow rate has a greater impact on R447A than on R410A. R447A necessitates a higher mass flow rate for equivalent refrigeration capacity. In addition, a novel model for R447A was proposed in this study, the predictive accuracy of the model ranges from -30.21% to +45.43%, with an average deviation of +5.21% and an absolute deviation of +10.96%. Notably, 90% of the predicted values exhibit deviations within ±20% of the experimental data.
Guo et al. (Fri,) studied this question.