BN-97-12-1 -- An Experimental Study of Heat Transfer Characteristics of New Alternatives to R502 PDF

Heat transfer characteristics such as heat transfer coefficient and pressure drop of new alternatives such as R507, R404a, R408a and the quarternary mixture R32/R125/R143a/R134a are presented and compared to R502. The steady-state data on heat transfer characteristics were obtained inside enhanced surface tubing with a heat transfer area of 0.05m² and the experimental setup was composed of a heat pump with 8kW capacity. Experimental data obtained during boiling and condensation tests show that R-507 has the lowest heat transfer rate compared to the refrigerant blends under investigation and R502. The boiling data demonstrated that R507 exhibited higher pressure drop than the refrigerant mixtures under investigation, including that of R502. However, the condensation data show that R404a has the highest pressure drop among the blends investigated.

Units: SI

KEYWORDS: year 1997, Heat flow, properties, refrigerants, mixtures, R502, R404a, R408a, R507, R32, R125, R143a, R134a, comparing, measuring, testing, experiment, heat transfer coefficient, pressure drop, boiling, condensation, fluorocarbons