The temperature of an electronics device rises fairly linearly with increasing device heat flux. This relationship is especially problematic for defense electronics, where heat dissipation is projected to exceed 1000W/cm in the near future. This paper study explored the benefit of cooling the electronics device using indirect refrigeration cooling system .In this system the heat sink in a prima...

in this study. optimum allocation of heat transfer inventory for heat exchangers in a refrigeration system with specified power input or cooling capacity. and for a heat pump with specified heating capacity is investigated. the ratio of hot- to cold-end conductance unit cost ratio. g.was considered in the analysis as an additional variable of considerable importance to the designer summarized e...

The impact of man-made chemicals on the environment, and in particular, the ozone layer, has been investigated over the last 20 years. The phaseout of CFCs under European Regulations and the Montreal Protocol has already taken place and HCFCs are set to follow. A wide range of alternative refrigerants with zero ozone depletion potential have already been developed as replacements for the refrig...

Authors Chaves and Viotto are with the Dept. of Food Technology. Direct inquires to Dr. Grosso, C.R.F. present address: Dept. of Nutrition, Food Engineering Faculty, State University of Campinas, S.P. Brazil, CEP 13083-970. ABSTRACT Each of three cheese batches was randomly divided into two parts, one was subjected to slow freezing for 15 days and the other maintained under refrigeration. There...

The relative low COP of transcritical CO2 systems caused by the throttle valve limited the further development. The replacement of a throttle valve with a turboexpander, an ejector or a vortex tube is leading to the way for improving the COP of a transcritical CO2 system. In this paper, a transcritical carbon dioxide refrigeration cycle with different expansion devices was analyzed theoreticall...

Long term storage of a variety of crops as well as long-distance transport, has allowed meeting the consumers’ expectations in the supply of many types of fresh fruits and vegetables throughout the year. This is only possible with the use of several postharvest technologies. This chapter starts with a brief historical context followed by an overview of the technologies used for fruits and veget...

A performance analysis on a vapour compression refrigeration system with various eco-friendly refrigerants of HFC152a, HFC32, HC290, HC1270, HC600a and RE170 were done and their results were compared with R134a as possible alternative replacement. The results showed that the alternative refrigerants investigated in the analysis RE170, R152a and R600a have a slightly higher performance coefficie...

Now a days, In most of the thermal power plant, where low-pressure steam is being exhausted to the atmosphere as a waste steam. This waste heat could be use to operate many small preheating or cooling equipments or small scale plants. There are many refrigeration systems present for refrigeration and air condition purpose. Such as air refrigeration, vapour compression, vapour absorption etc. In...