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...

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...

Experimental investigation was done to find the role of capillary tube length and amount of refrigerant charge on the overall heat transfer coefficient in condenser and evaporator and actual COP of a simple vapour compression refrigeration system. It was concluded that increasing of the refrigerant charge in the system largely enhances the overall heat transfer coefficient in the evaporator by ...

The selection of proper refrigerants for natural gas liquefaction processes play a key role in cycle?s efficiency. Mixed have been proven to improve exergy efficiency over single pure refrigerant. However, the future some these with higher global warming potential index are unknown due continuous restriction being enforced by energy and environmental agencies past few decades. This study examin...

In the present paper an analysis of mixed convection of an unsteady magneto hydrodynamic (MHD) flow of an incompressible viscous fluid through porous media due to a vertical porous stretching sheet in the presence of viscous dissipation, thermal radiation and heat source /sink has been carried out. The fluid considered is viscous and incompressible. The governing partial differential equations ...

An experimental investigation was implemented to determine the capacity degradation due to non-uniform refrigerant and air flow distributions, and to assess the potential to recover the lost capacity via controlling refrigerant distribution between individual refrigerant circuits. The tests were performed on a three-circuit, threedepth-row, finned-tube evaporator. Refrigerant inlet quality, exi...

This paper presents a surrogate-assisted framework to solve constrained black-box optimization problems, which is applied the optimal single-mixed refrigerant natural gas liquefaction processes design. approach uses kriging models as cheap-to-evaluate, reliable surrogates of process-simulator-dependent functions problem. From prediction and estimated error, probability feasible improvement acqu...

The use of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) has been widely restricted. They have been replaced with hydrofluorocarbons (HFCs) in order to protect the ozone layer. However, the leakage of refrigerant into the air from active or end-of-life air conditioners is a serious environmental issue owing to the high global warming potential (GWP) of HFCs. Therefore, replaci...