In-tube flow-boiling experiments for two new zeotropic, three-component refrigerant mixtures (402A and R404A) and R502 have been carried out. Comparative results show that local flow-boiling heat transfer coefficients for R404A are slightly larger than those for R502 under the same test conditions, while those for R402A are on average slightly smaller. The heat transfer performances of the three fluids are accurately predicted by an existing flow-boiling correlation modified here to include analytical, mass diffusion mixture boiling equation.

KEYWORDS: year 1995, refrigeration, replacing, R502, R402A, R404A, mixtures, experiment, fluid flow, boiling, heat transfer coefficient, testing, heat flow, performance, calculating, comparing.