This paper indicates how ammonia systems might be adapted to make them more suitable for use on installations which traditionally adopted CFC and HCFC refrigerants in the range 100kW – 600kW cooling capacity for warehouses, blast freezers and food factory applications. The examples draw on over twenty years of experience with low charge systems in Europe, but are specifically focussed on the Am...

This paper presents the results of an experimental study on capillary tubes commonly used as expansion device in household refrigerators and freezers. The experiments were performed with HFC-134a at different condensing pressures and level of subcooling. The pressure and temperature profiles along the capillary tubes were measured in each test run. The data set was then used to evaluate the sui...

Refrigeration is one of the leading uses of electric power in the United States. The term "refrigeration" refers to air-conditioning for homes, businesses, and industry and the operation of refrigerators, freezers, and heat pumps. The technology most often used in refrigeration, the vapor compression cycle, is 100 years old, inefficient, and environmentally unsound. Since the 1980s, the refrige...

We developed a questionnaire to assess motor imagery (MI) of gait and administered it to 33 controls and 28 individuals with PD. Our goals were: 1) compare gait MI in individuals with and without PD, 2) determine whether walking performance relates to gait MI and 3) compare gait MI in individuals with PD with and without freezing of gait. Gait MI was not different between PD and controls. There...

In the first part of the present research, an R290/R600 mixture was tested as a drop-in substitute in a 20cubic-feet, single-evaporator, autodefrost, topmount, conventional domestic refrigerator/freezer. All the hardware remained the same, only the capillary tube was lengthened to achieve the optimum performance. The best result with an optimized R290/R600 blend was 6% savings compared to the b...

Refrigeration is one of the leading uses of electric power in the United States. The term "refrigeration" refers to air-conditioning for homes, businesses, and industry and the operation of refrigerators, freezers, and heat pumps. The technology most often used in refrigeration, the vapor compression cycle, is 100 years old, inefficient, and environmentally unsound. Since the 1980s, the refrige...

This work presents an experimental approach to study the refrigerant flow through capillary tube-suction line heat exchangers. Lateral heat exchanger performance with refrigerant HFC-134a was experimentally evaluated for a range of heat exchanger assemblies and operating conditions typically found in household refrigerators and freezers. Based on the resulting performance data base, the influen...

Until now the rotating and oscillating imbalance in the hermetic compressor has been balanced to and greater or lesser extent, but in addition internal springs were added where this was expedient from a design viewpoint. It is clear, however, that the position of the springs is an important factor in the transmitted vibrations. Generally, it proves in this paper that for a single-cylinder compr...