This paper introduces the dual-mode refrigeration system for ice storage air conditioning. A computational model relating to the exergy loss amount and loss rate is developed in each component of the refrigeration cycle loop. A case study is presented to demonstrate the applicability of the model developed. Exergy analysis results of the refrigeration system in ice storage operating mode are co...

A. 1 ohansson and P. Lundqvist Dept. of Energy Technology Div. of Applied Thennodynamics and Refrigeration The Royal Institute of Technology, KTH Stockholm, Sweden Test results from field retrofit situations, where R22 has been changed to Isceon 59 1 and R407C in two identical chillers, shows that both substitutes require more subcooling than R22 to give the system a satisfying performance. It ...

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...

Ammonia can be applied to any type and size of refrigeration system from domestic refrigeration to commercial refrigeration and air-conditioning to industrial refrigeration. However, it is desirable to minimize the charge to prevent toxic effects and, sometimes to use secondary refrigerants, such as volatile carbon dioxide, to keep ammonia away from the general public. This article describes a ...

  In this study, fluid flow and energy separation in a micro-scale Ranque-HilschVortex Tube are numerically investigated. The flow is assumed as 2D, steady,compressible ideal gas, and shear-stress-transport SST k-W is found to be a bestchoice for modeling of turbulence phenomena. The results are in a good agreementwith the experimental results reported in the literature. The results show that f...

â liquefied natural gas (lng) is the most economical way of transporting natural gas (ng) over long distances. liquefaction of ng by using vapor compression refrigeration system requires high operating and capital cost. due to lack of systematic design methods for multistage refrigeration cycles, the conventional approaches of determining optimal cycle configuration are mostly based on trial-an...

The purpose of this paper is to introduce the development of a unique compressor capacity modulation concept which utilizes reexpansion volume as a means of capacity reduction in hermetic air conditioning and refrigeration system. While there are various methods of compressor capacity modulation in use, each particular method is limited in its application or appeal for different reasons such as...

Compressor performance is ioiluenced by many factors. Besides the commonly considered factors such as suction gas heating, leakage, compressed gas re-expansion, gas pulsations, and back flow, supercharging effect on performance is also studied. Since the compressor used in this study operates in a wide speed range, from 1100 rpm up to 9000 rpm, how those factors affect the compressor performanc...

Magnetic refrigeration is a fascinating superior choice technology as compared with traditional that relies on unique property of particular materials, known the magnetocaloric effect (MCE). This paper provides thorough understanding different magnetic technologies using variety models to evaluate coefficient performance (COP) and specific cooling capacity outputs. Accordingly, are divided into...

This review discusses the progress and ongoing efforts in optical refrigeration. Optical refrigeration is a process in which phonons are removed from a solid by anti-Stokes fluorescence. The review first summarizes the history of optical refrigeration, noting the success in cooling rare-earth-doped solids to cryogenic temperatures. It then examines in detail a four-level model of rare-earth-bas...