An overview for the heat transfer performance of HFO-1234yf

摘要

This study provides an overview about the two-phase heat transfer performance for HFO-1234yf which is made to substitute R-134a. Based on the limited information, it is found that the nucleate boiling heat transfer coefficient (HTC) and convective boiling HTC for HFO-1234yf are comparable to R-134a provided q < 200 kW m~(-2). The critical heat flux for HFO-1234yf is about 20-40% lower than that of R-134a. For external condensation, the only database shows that the HTC between HFO-1234yf and R-134a is also negligible. However, it is found that the major thermophysical properties influencing condensing HTC suggest a lower HTC of HFO-1234yf. For in-tube condensation, it is found that the condensation HTCs for HFO-1234yf are inferior to those of R-l34a, and the difference increases with the rise of vapor quality. The predictive correlations applicable for pressured drop for HFO-1234yf are not consistent, it is probably attributed to the difference in tube diameter in the publications.