In this paper, exergy analysis is used to evaluate the performance of a combined Cycle: organic Rankine Cycle (ORC) and Absorption cooling system (ACS) using LiBr–H2O, powered by a solar field with linear concentrators.The goal of this work is to design the cogeneration system able to supply electricity and ambient cooling of an academic building and to find solutions to improve the performance of the global system. Solar ACS is combined with the ORC system-its coefficient of performance depends on the inlet temperature of the generator which is imposed by the outlet of the ORC. Exergetic efficiency and exergy destruction ratio are calculated for the whole system according to the second law of thermodynamics. Exergy analysis of each sub-system leads to the choice of the optimum physical parameters for minimum local exergy destruction ratios. In this way, a different connection of the heat exchangers is proposed in order to assure a maximum heat recovery.

In this study, the thermoeconomic performance of Absorption refrigeration Cycle utilizing binary solution containing water-ionic liquid (1-Ethyl-3-Methylimidazolium Trifluoroacetate) is investigated and compared with the water-lithium bromide Cycle. For this purpose, the thermodynamic and thermoeconomic analysis have been employed to simulation of the Cycle and then, the effects of design parameters on the performance parameters like coefficient of performance, exergetic efficiency, solution circulation flow ratio, area of heat exchangers and cost of the streams are studied. The thermodynamic properties of the binary solution are predicted using Non-Random Two Liquids model. It has been found the system with ionic liquid has a lower coefficient of performance and exergetic efficiency (0. 66, 10. 15%) than aqueous solution of lithium bromide system (0. 78, 12 %). The total area and total cost of the ionic liquid system (49 m2, 4907 $/year) is larger than water-lithium bromide Cycle (16 m2, 3347 $/year). Despite the Lower performance of systems with ionic liquid, the advantages of these liquids like no crystallization, negligible vapor pressure and weak corrosion tendency to iron-steel materials make the new working pair suited for the Absorption refrigeration Cycle.

The use of solar energy in the refrigeration Cycle is one of the newest ways to increase the coefficient of performance and use of clean energy. The purpose of this paper is to present a parametric simulation and the performance analysis of a water-lithium bromide Absorption refrigeration Cycle equipped with a solar receiver in terms of thermodynamics and exergy. The effect of different parameters on system efficiency, heat transfer rate in generator, exergy efficiency and exergy changes of the whole system is investigated. The results of the study show that there is an optimal radiation intensity at a given temperature for the evaporator and condenser, in which the total exergy changes of the system are minimized and the system coefficient of performance and its exergy efficiency reach its maximum. The results show that when the evaporator temperature is in the range of 4 to 10 ° C and the condenser temperature is in the range of 33 to 39 ° C, the maximum yield coefficient for the single-Cycle Cycle is in the range of 0. 75 0 to 80/0. Also, surveys show that the maximum exergy efficiency for a single-Cycle refrigeration Cycle is in the range of 13 to 23. 7 percent.

In recent years, the use of Gas Turbine-Modular Helium Reactor (GT-MHR) which operates in accordance with closed Brayton Cycle with helium fluid as working fluid has attracted researchers’ attention because of its high efficiency, high reactor safety, being economical, and low maintenance costs. In the present study, a combined system, including GT-MHR Cycle, Kalina Cycle and Ammonia-water Absorption Cycle is investigated with respect to energy, exergy, and exergoeconomic. As the bottoming Cycle, Kalina Cycle and Absorption Cycle are used in order to avoid energy wasted by gas turbine Cycle and to increase efficiency of energy conversion. The results of the simulated model show that, in the basic input mode, the overall work is 304462 kW, the overall exergy destruction is 289766kW and the overall exergy efficeincy of cogeneration Cycle is 0. 689kW. Also reactor, turbine and compressor in helium Cycle are the component to which more attention should be paid with respect to exergoeconomic because the highest amount of cost rate is related to these components. At the end, parametric analysis is carried out in order to evaluate the effect of the changing pressure ratio of helium compressor, input temperature of helium compressor, input pressure and temperature of turbine and mass fraction of the base mode of the Kalina Cycle on the output parameters.

A detailed modular modeling of an absorbent cooling system is presented in this paper. The model including the key components is described in terms of design parameters, inputs, control variables, and outputs. The model is used to simulate the operating conditions for estimating the behavior of individual components and system performance, and to conduct a sensitivity analysis based on the given control variables. The proposed model has been validated by means of comparing the predicted results with the experimental data in a full-scale absorbent cooling system installed at MERC. Careful attention was given to estimate the behavior of the system at transient mode. Based on operating conditions, a range of time-constant start-up time had been estimated for generator and evaporator. The results indicated that the model predictions were in good agreement with experimental data. Sensitivity analysis also showed that the performance characteristics of the system could be approximated by generalized polynomial functions of order 2 in terms of control variables. Finally typical performance results are discussed.

Using renewable energy sources as a solution for country⠀™s stable growth needs distinct look in topics of energy production. Agriculture industry is a general industry and it is an energy consumer that can be considered as a topic in this field. Existing a based refrigerator in farm and garden makes optimized harvesting and because it is easy to use sun radiation at these places, it can be used as a source of energy for providing refrigerator⠀™s energy. One of important needs in refrigerator, is producing continues and stable effect of refrigeration in operator while radiation release is intermittent and variable. By presentation of synthetic Cycle of absorbing refrigeration, liquid refrigerant can be stored during radiation, so it can be used in other situations and as a result continues and stable effect of refrigeration can be produced. Considering collector⠀™s parabolic shape optimized temperature, 119. 6 ° C in generator is available. Optimized temperature of condenser, absorber and operator, in order equals 40, 43. 7 and-3. 2 ° C. By selecting 14bars for pressure in generator and condenser and 2bar pressure for operator and absorber, maximum coefficient of operation is 0. 178 and rate of heat transfer in generator, condenser, absorber and operator is achieved 19. 76, 7. 51, 15. 77 and 3. 51 Kw in order.

In this article, a combined GAX-ejector Absorption refrigeration Cycle is proposed and its performance is compared with those of combined single effect-ejector, simple GAX and single effect Absorption refrigeration Cycles. For the ejector, based on the Keenan's theory, a new model is developed and validated and then is combined with the developed models in the EES software (for simulating the processes in the Cycles). After obtaining the optimum critical area ratio for the ejector, three different ejectors, with the mentioned specification, are selected for the combined GAX-ejector and combined single effect-ejector Cycles. The performance of these Cycles is investigated through changing their evaporator and generator temperatures. Results indicate that, at identical conditions, the COP and second law efficiency of the combined GAX-ejector Cycle are around 25% and 16% higher than those of the combined single effect-ejector Absorption refrigeration Cycle. In addition, it is observed that as the generator temperature increases from 140oC to 170oC, the COP and second law efficiency of combined GAX-ejector Cycle are maximized at a particular generator temperature. However, at similar condition, an increase in generator temperature results in a decrease of the COP and second law efficiency of combined single effect-ejector refrigeration Cycle. Moreover, it is revealed that the ejector has the second highest contribution (after generator-absorber assembly) in the total exergy destruction.

This research investigates an HDH humidifier-dehumidifier Cycle that incorporates a direct contact dehumidifier and a single-effect solar Absorption refrigeration system (ARS). Due to its utilization of biomass, solar energy, and geothermal energy for chilling purposes, Absorption refrigeration systems are being examined for their environmentally friendly design. The system's performance was evaluated across several operational scenarios by employing a mathematical model. In order to incorporate the impact of humidification and dehumidification units into the theoretical modeling, the correlation was employed to examine the heat and mass transport in the system under consideration. The system's performance was evaluated using performance parameters such as recovery ratio (RR), coefficient of performance (COP), and output gain ratio (GOR). An investigation was conducted on the state of the hybrid HDH system in conjunction with an Absorption refrigeration system, considering various cooling situations. Studies have demonstrated that modifying the ratio of saline water to fresh water or saline water to dry air in an HDH system allows for the integration of an Absorption refrigeration system of the water-ammonia type, without requiring extra cooling load. This adjustment successfully achieved a favorable recovery ratio. In order to prevent the requirement for extra cooling, the system can be initiated within the range of values that are less than 2.5 and greater than 4.2.

In recent years, a growing emphasis has been on providing sustainable energy to reduce carbon emissions and promote energy efficiency. This article aims to investigate thermodynamic and exergoeconomic analyses of the cascade Absorption refrigeration with a vapor compression refrigeration system driven by a geothermal renewable energy source. The purpose of this system is to produce four different products: power, heating load, cooling, and fresh water. The effect of temperature and mass flow rate parameters of the geothermal source, fresh air ratio parameter, condenser temperature, evaporator-condenser outlet temperature of the Absorption refrigeration section, and the evaporator temperature of the vapor compression refrigeration system on the essential decision variables of the system and also on the temperature provided for the thermal comfort of the house and The flow of fresh water produced by the fan coil unit is provided, which has the most influence on the decision parameters, is caused by the output temperature and mass flow rate of the geothermal energy source. The system output parameters such as COP, W ̇_net, η_energy, η_exergy and SUCP in the basic mode are equal to 0/35, 9/78kW, 73/5%, 32/25%, and 101/11$/GJ respectively. The highest exergy destruction occurs in the geothermal reinjection, with an amount of 53% of the total exergy destruction. The calculations performed in this research were done in the EES software.