EXPERIMENTAL COMPARISON OF ECO-FRIENDLY REFRIGERANT COUPLES R407C/R32/R600a (90/10 BY WT.%) AND R407C/R32 TO REVEAL THE GWP AND THERMODYNAMIC PROPERTIES

Abstract

In this experimental study, based on cooling couples a new mixture (90%R32 + 10%R600a) has been proven to be better than R32 for the global warming potential (GWP) in a low-pressure cycle (LPC), within a high-pressure cycle (HPC) R407C by utilizing a small laboratory cooling system. This system consists of two cooling cycles connected by a heat exchanger and has also been termed as a mini cascade refrigeration system (MCRS). The main aim of this study is to study a suitable gas or mixture for MCRS at the lowest GWP value and a low-temperature cooling room to reach less than -30°C. In the same way, the following conditions have been determined in this research: the inlet and outlet temperatures of the evaporator, condenser, heat exchanger, compressors, with evaporator pressure as well as superheat. Consequently, MCRS can be used with thermostats at the lowest degree of -32°C or less, the mixture has results close to R32 and the coefficient of performance for MCRS COPMCRS is equal to 1.63 and 1.78 for the new mixture and R32, respectively, under the same operating conditions. Therefore, the ozone depletion potentials (ODP) for R32 and the new mixture are equal to zero, and the GWP for the new mixture is less by amount of 63 than that for R32. The MCRS can be used in a small place, for instance, transport blood samples, blood tests, and vaccines by small cars. Both R32 and R600a are flammable gases, so this study will be carried on in the future for safer replacements.