It is well-known that HCFC refrigerants widely used in today’s air conditioning and refrigeration (AC&R) industry will soon be phased out, mainly due to their ozone depletion potentials (ODPs) and global warming potentials (GWPs). The timetable established through international agreement and national legislation calls for a 65% reduction of HCFC consumption based on 1989 level by January 1, 201...

Measurements on R600a refrigerators have shown electricity savings over R134a and R12 up to 20%. We propose new parameters which are functions of well known refrigerant properties. These parameters show that R600a has half the leakage, pressure loss and condenser pressure and double the heat transfer coefficient of R12 and R134a explaining the measurements. Use of R600a in small heat pumps and ...

In recent years, increasing attention has been focused on the use ofhalogenated hydrocarbon mixtures as working fluids in vapor compressionrefrigeration systems, e.g. heat pumps. This paper discusses phase rules,applied to the equilibrium of the vapor and liquid states of such mixtures.Mixtures of ideal behavior, those that obey Raoult's law, and those withdeviations from th...

This paper presents a comparable evaluation of R600a (isobutane), R290 (propane), R134a, R22, R410A, and R32 in an optimized finned-tube evaporator, and analyzes the impact of evaporator effects on the system coefficient of performance (COP). The study relied on a detailed evaporator model derived from NIST’s EVAP-COND simulation package and used the ISHED1 scheme employing a non-Darwinian lear...

The results obtained from the exergoeconomic and exergy analysis of a model generic air conditioning (A/C) system without with an membrane exchanger using three commercially available refrigerants: R410A, R407C, R134a, are reported. used specialized software that was validated against recently published data showed good agreement. A/C systems energy intensive consume significant portion global ...

In consideration of physical and chemical properties of pure substances, speed of sound is one of important quantity which can used to calculate many of other thermo-physical properties such as isothermal compressibility, Joule-Thomson coefficient, isobaric heat capacity and etc. These thermo-physical properties are the main parameters in industrial and chemical processes. Development of accura...

Thermodynamic data on environmental refrigerants have attracted considerable interest in the optimization and design of heat compressors, exchangers and other refrigeration equipment. In this study, An optimization algorithm was used to obtain the constant parameters of the new empirical model by fitting them to the source databank. The model was used to calculate the constant coefficients of t...

Vle have developed a predictive corresponding states model for the thermo· physical properties of pure refrigerants and refrigerant mixtures. The bulk phase properties such as the density, enthalpy and entropy are predicted using the prin· ciple of extended corresponding states. This theoretically based model uses shape factors to insure conformality among the various components and R134a is us...

In recent years the household compressor manufacturers have reduced the energy losses inside the compressors resulting in a positive effect on the energy consumption in the cabinets. In the following, N-butane, which is a natural and non ozone depletion refrigerant, is compared to refrigerants presently used in household compressors.