in this paper, the effects of input temperature and compression ratio on the net output work and efficiency of the air standard cycles, i.e. atkinson cycle, diesel cycle and otto cycle are analyzed. we assumed that the compression and power processes are adiabatic and reversible and any convective, conductive and radiative heat transfer to cylinder wall during the heat rejection process may be ...

In this paper, an experimental work was investigated on nanorefrigerant .Nano Al2O3-PAG oil was used as nano-refrigerant in R134a vapour compression refrigeration system . An experimental setup was designed and fabricated in the lab. The system performance was investigated using energy consumption test and freeze capacity test. The results indicate that Al2O3 nano refrigerant works normally and...

Capacity and efficiency of any refrigerating system diminish rapidly as the difference between the evaporating and condensing temperature is increased by reduction in the evaporator temperature. The single stage vapour compression refrigeration system is limited to an evaporator temperature of -40 C. Below temperature of -40 C the either cascade refrigeration system or multi stage vapour compre...

Capacity and efficiency of any refrigerating system diminish rapidly as the difference between the evaporating and condensing temperature is increased by a reduction in the evaporator temperature. The single stage vapour compression refrigeration system using various refrigerants are limited to an evaporator temperature of -40 0C. Below temperature of -40 0C the either cascade refrigeration sys...

iran’s vast common natural gas resources and the necessity to extract and export it as liquefied natural gas (lng) to distances more than 3000km opens a lucrative field for researchers to optimize lng cycles. in this article heat integration in cryogenic cycles by determining interacycle partition temperature and optimizing refrigeration features like subcooler, presaturator, aftercooler, reboi...

As a requirement for sustainable development, air-cycle refrigeration has received wide attention as candidate environmentally friendly air conditioning technology. In this study, the thermodynamic performance of cycles is investigated in compartment conditioning. The effects compressor efficiency, expander ambient humidity, all-fresh-air supply and pressure on cycle are presented. arrangement ...

Refrigeration is an essential part of the food chain. It used in all stages chain, from industrial processing to final consumption at home. In these processes, mechanical refrigeration technologies are employed, where compressors increase gas pressure evaporation condensation. systems, twin-screw represent most widely technology. A detailed mathematical model a compressor has been developed Sim...

Exergy is precious energy. On the basis of thermodynamic analysis of thermal processes, one can choose more exergy-saving devices. This is especially important in refrigeration processes, in which the consumption of energy and exergy increases considerably with the falling cooling temperature. The exergy efficiency in terms of exergy losses of vapour compression and sorption cooling processes i...

An adsorption system driven by solar heat or waste heat can help to eliminate the use of ozone depletion substances, such as chlorofluorocarbons (CFCs) and hydro-chlorofluorocarbons (HCFCs). In recent years, adsorption system has witnessed an increasing interest in many fields due to the fact that this system is quiet, long lasting, cheap to maintain and environmentally benign. Although adsorpt...

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...