RESULTS OF EXPERIMENTAL AND THEORETICAL-STUDIES OF THE AZEOTROPIC REFRIGERANT R507

For a blend containing R143a and R125 (50/50% by weight), thermodynami c data like vapour pressures, liquid densities, as well as the volumet ric behaviour of the gaseous phase, have been experimentally measured and mathematically correlated. This refrigerant blend shows azeotropic behaviour and is known as R507 according to the ASHRAE nomenclature. For use in refrigeration and air-conditioning units in low and medium temperature applications, R507 is a suitable refrigerant. Test results based on measurements from a refrigeration installation have shown th at similar operating parameters can be achieved in comparison to R502. The compressor discharge temperatures, pressure ratios and coefficien ts of performance compare well to the traditionally used azeotropic re frigerant R502. Further, the tests have shown that on average the refr igerating capacities of R507 are approximately 5-6% higher than the ca pacities of R502. (C) 1997 Elsevier Science Ltd and IIR.