Energy and exergy analyses were carried out for a pilot parabolic solar dish-Stirling System. The system was set up at a site at Kerman City, located in a sunny desert area of Iran. Variations in energy and exergy efficiency were considered during the daytime hours of the average day of each month in a year. A maximum collector energy efficiency and total energy efficiency of 54% and 12.2%, res...

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...

This study presents an experimental comparison of energy, exergy flow and second law efficiency of R22 and its substitute R436b (hydrocarbon mixture of 52% of propane (R290) 48% of isobutene (R600a)), vapour compression refrigeration cycles. The vapour compression refrigeration cycle was initially designed to operate with R22. The primary objective of this paper is to analyze the system process...

Usually efficiency is defined in energetic terms without taking into account the quality of the energy. Another way to analyse and optimise processes and systems is in terms of exergy. The concept of exergy incorporates both qualitative and quantitative properties of energy. Exergy analysis makes the exact determination of the energetic and resource saving potential of industrial processes or s...

An energy flow model of an airport terminal’s HVAC system is established in this paper. Based on energy flow model, the exergy efficiency, exergy loss and exergy cost distribution ratio of each component are calculated and analyzed by the energy flow model. Optimization method and exergy balance equations are used to calculate the lowest exergy loss of HVAC system under different operation cond...

exergy analysis of a system is a method for recognizing the value and type of system availability against surrounding environment. it also helps to find how macroscopic properties of the system change during a process. this analysis is based on first and second laws of thermodynamics. by exergy analysis proportion of each process in the internal availability transmission and the places of usefu...

A single vacuum tube based solar cooker has high energy and exergy efficiency, and is capable of achieving cooking temperatures as high as 250 C. The reason for high energy and exergy efficiencies of this solar cooker is the high achievable concentration ratios of 15e20, which are not possible with multiple vacuum tube based solar cookers. In this paper, a comparative study has been carried out...

exergy analysis of an integrated molten carbonate fuel cell-turbo expander-steam turbine hybrid cycle has been presented in this study. the proposed cycle has been used as a sustainable energy approach to provide a micro hybrid power plant with high exergy efficiency. to generate electricity by the mentioned system, an externally reformed molten carbonate fuel cell located upstream of the combi...

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...

Thermoeconomic diagnosis of refrigeration systems is a pioneering approach to the diagnosis of malfunctions, which has been recently proven to achieve good performances for the detection of specific faults. Being an exergy-based diagnostic technique, its performance is influenced by the trends of exergy functions in the “design” and “abnormal” conditions. In this paper the sensitivity of perfor...