The given paper is aimed at constructing the general circuit of heat processes in a semihermetic reciprocating refrigerant compressor as a basis of application of new ecology-friendly refrigerants as well as optimizing design parameters of compressor. While performing this work the following problems were solved: 1. Experimental research of heat processes in a semihermetic refrigerant reciproca...

This paper presents the heat transfer coefficients and the pressure drop measured during HC-600a (Isobutane) condensation inside a brazed plate heat exchanger: the effects of saturation temperature, refrigerant mass flux and vapour super-heating are investigated. The heat transfer coefficients show weak sensitivity to saturation temperature and great sensitivity to refrigerant mass flux. At low...

The refrigerant release technology relieves even eliminates the over-compression loss of scroll compressor by bypassing the refrigerant in the compression chamber to the suction pipe under small system pressure ratio conditions. Because the room air conditioner works in mild conditions at most of the time, its seasonal energy performance is expected to be effectively improved by the refrigerant...

Performance of a reciprocating refrigerator compressor with mixed-refrigerants (MR) was investigated experimentally. The current, standard methods of testing compressors and presenting performance data were found unsuitable for MR, and a new experimental apparatus was designed for a ·direct flowrate measurement with MR. Representative test data for Refrigerant R-12 and for a mixture of R-22/R-1...

The interest in application of secondary refiigerant systems in supermarket refrigeration is increasing. Reduced refrigerant losses i and the chance for lower installation and operation costs is promoting this development. There are also !options to use natural refrigerants, more efficient refrigerants and gas or waste heat driven absorption proc;esses. First installations of secondary refriger...

The U.S. is strongly considering regulating hydrofluorocarbons (HFCs) due to their global climate change forcing effects. A drop-in replacement hydrofluoroether has been evaluated using a gate-to-grave life cycle assessment of greenhouse gas emissions for the trade-offs between direct and indirect carbon dioxide equivalent emissions compared to a current HFC and a historically used refrigerant....

A cold room assisted vapor-compression refrigeration cycle is dynamically modeled in a year and optimized. Total annual cost (TACO) and coefficient of performance (COP) are selected as two objective functions. Both cold room and refrigeration cycle parameters are considered as design variables. Moreover, three working fluids included R22, R134a and R407c are examined. The optimum Pareto front r...

A New-PVE lubricant was developed for use with R32 refrigerant. R32 has been proposed as an alternative refrigerant for R410A refrigerant, to reduce global warming. In this report, we evaluated the relationship between the New-PVE lubricant and R32 and R410A refrigerants. The evaluation items were physical properties (miscibility, solubility, mixture viscosity and volumetric resistivity) and th...