four kinds of refrigerant mixtures R22/Rl34a, R22/Rl52a, R22/Rl42b and R22/Rl23, which contain some new halocarbons which are considered to be the alternatives for CFCs, were evaluated in order to realize higher condensing temperature than that using R22 at high temperature operation, and larger heating capacity than that using R22/Rll4 at normal temperature operation. These mixtures were appli...

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...

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...

Over the last thirty years, few changes have taken place in reciprocating refrigeration and freezer hermetic· compressors. Of course there have been design improvements and many new applications, but the basics have stayed the same. DOE requirements have brought new energy standards for 1993 and, with most of that work behind them, manufacturers of white goods are concentrating on alternate ref...

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 ...

Alternate Reality Games (ARGs) are a new genre of transmedia practice where players collaboratively hunt for clues, make sense of disparate information, and solve puzzles to advance an ever-changing narrative that is woven into the fabric of the real world. This paper highlights the potential for ARGs to promote 21 Century literacy skills. We propose a meta-level framework for 21 century litera...

Gamication—the use of game mechanics in conventionally nongame activities— has received attention in the eld of education. Games, however, are not reducible to the common mechanisms of gamication that target extrinsic motivation, and may also include elements such as role playing, world making, and collective storytelling. Here, the authors discuss the potential learning benets of largescal...