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The original version of this article unfortunately contained a mistake. The affiliation of the second author was incorrect. The correct information is given below: Hadi Ghaebi, Department of Mechanical Engineering, Faculty of Engineering, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran. © 2018, The Brazilian Society of Mechanical Sciences and Engineering  

Bi-evaporator electricity/cooling cogeneration systems can be a favorable addition to the integrated power plants since the generated cooling load should be addressed for different demands. More consequentially, taking advantage of such an integral set-up operated with highly reliable heat source such as biogas can be appreciable for nowadays industries. Regarding this demand, an innovative bi-evaporator electricity/cooling cogeneration system is introduced at first. Next, the suggested system is integrated with a gas turbine cycle fueled by biogas. In the subsequent part, the plausibility of the introduced integrated power plant is examined from first and second laws of thermodynamics (as... 

An innovative bi-evaporator electricity/cooling cogeneration system fueled by biogas is introduced. The plausibility of the introduced integrated power plant is examined from thermodynamic and economic vantage points. Later, single- and multi-objective optimization of the reckoned system are achieved by selecting appropriate parameters as decision variables and thermal and exergy efficiencies and total unit product cost (TUPC) of the system as objective functions. Four optimum modes of thermal efficiency optimum design (TEOD), exergy efficiency optimum design (EEOD), cost optimum design (COD), and multi-objective optimum design (MOOD) are selected for optimization and the attained results... 

Despite the fact that humidification-dehumidification (HDH) desalination systems can be driven by various renewable or waste heat energies, many of the available renewable technologies are expensive in some parts of the globe. Hence, proposing and developing high-efficient mechanical-based HDH units can be an encouraging alternative which is more highlighted in recent investigations. In pursuance of this objective, three innovative mechanical-driven HDH units are simulated and the results are compared with each other. The simulated hybrid desalination system consists of a HDH unit and an ethane ejector expander transcritical refrigeration cycle (ethane-EETRC). The simulated hybrid systems... 

Among different types of geothermal processing used in the energy conversion systems, flash-binary geothermal can be the best scenario for high-temperature geothermal sources. Reviewing the available literature it can be found that the flash-binary geothermal power plants have a great potential to be extended to trigeneration systems, nonetheless they have received less attention. In this regard, a new trigeneration system for freshwater, power, and cooling production is devised using a flash-binary geothermal heat source at 170°C. In this devised trigeneration system, a humidification-dehumidification (HDH) unit is used as a binary cycle. Another merit of the devised trigeneration system is... 

Anaerobic fermentation of crop straw/animal dug can be the most appropriate solution for biomass conversion into applicable renewable energy-based fuels. However, due to the imperfection matching between the biogas combustion process and energy conversion system, a painstakingly design procedure is required to devise high-efficient energy system for capturing biogas efficiently. For this aim, a new trigeneration system driven by biogas is devised for electricity, refrigeration, and potable freshwater generation. The devised system encompasses a gas turbine (GT) cycle, a new cooling/electricity cogeneration system based on organic Rankine cycle (ORC) and ejector cooling cycle (ECC), and a... 

A new combined cooling and power (CCP) cycle is proposed by a novel combination of the Kalina cycle (KC) and ejector refrigeration cycle (ERC) to produce simultaneous power output and cooling output. The exhaust of the turbine is fed to the ejector as a primary flow to draw the secondary flow (outlet of the evaporator) into the ejector. Energy, exergy, and exergoeconomic analysis of the proposed cycle are carried out leading to determine the first-law-efficiency, the second-law-efficiency, the sum unit cost of the product (SUCP) of the system, and the main source of the irreversibility. The thermal efficiency, exergy efficiency, overall exergy destruction rate, SUCP of the system, net... 

Exploration of the ejector refrigeration cycle (ERC) in the combination with well-known power cycles to produce cooling output as well as power output is highlighted in recent decades. Since organic Rankine cycle (ORC) is practically usable than other power cycles, a combination of the ORC/ERC in a novel form is presented. Power and refrigeration sub-cycles are combined by a common condenser in separate loops to form dual-loop power/refrigeration cycle. The exhaust of the turbine is mixed with the outlet flow of the ejector, and then the mixed flow is fed into the condenser. Thermodynamic and thermoeconomic analysis of the proposed cycle are carried out with different working fluids (i.e.,... 

Purpose: The purpose of this paper is to derive a closed-form expression for the steady-state availability of a cold standby repairable k-out-of-n system. This makes the availability calculation much easier and accurate. Design/methodology/approach: Assuming exponential distributions for system failure and repair, the Markov method is employed to derive the formula. Findings: The proposed formula establishes an easier and faster venue and provides accurate steady-state availability. Research limitations/implications: The formula is valid for the case when the probability density function of the component failure and the repair is exponential. Originality/value: The Markov method has never... 

A precise heat transfer simulation of a three-dimensional impinging jet porous heat sink is presented and is analyzed from thermodynamics vantage point under local thermal non-equilibrium condition. To increase the computational efficiency of the analysis, pore-scale modeling based on lattice Boltzmann method (LBM) is used inside the porous media (at a meso-scale), whilst finite volume method (FVM) is employed around it (at a macro-scale). The effects of the Reynolds number, porous layer thickness, solid/fluid thermal conductivity ratio, and porosity on the critical heat transfer and entropy generation parameters are investigated. Additionally, the relations between viscous entropy... 

Multi-effect distillation units discard brine at high volume to the environment which results in numerous environmental pollutions, low thermodynamic performance, high exergy destruction rate, and high unit cost for the fresh water. This study aims at introducing a new method of pre-treatment for the brine discarded from each stage of the desalination plant to increase its concentration. The new method per-concentrates the brine by superheating the steam produced in the previous stage via recovering valuable thermal heat of the same effect. Due to a low temperature difference between the heat sink and heat source of this self-superheating scheme (i.e., the temperature difference between the... 

In this study, four new indirect heat pump assisted mechanical vapor compression humidification-dehumidification (HDH) systems are proposed and their superiorities over the reference system are demonstrated from thermodynamics and thermoeconomics viewpoints. The proposed models are configured based on an HDH unit and a simple cascade heat pump, an HDH unit and a heat pump with an ejector, an HDH unit and a cascade heat pump with an ejector, and an HDH unit and a vapor injection heat pump. Although employing a heat pump with cascade and ejector configurations improved gain-output-ratio (GOR) and specific power consumption (SPC) values in comparison with the base system, the performance... 

Global issues arising from water and electricity shortages have notoriously affected social life over the last decades. In this regard, using renewable energy sources like waste heat of wind turbines (WTs) to drive desalination systems can be a promising solution. However, high specific work consumption (SWC) for desalinating seawater from the waste heat of the wind turbine generator can hinder the application of this new emerging technology. To address this problem, a multi-effect distillation mechanical-vapor compression (MED-MVC) desalination unit is used to recover the brine rejected from a humidification-dehumidification (HDH) desalination unit operating by the waste heat of the... 

Feasibility investigation of a humidification dehumidification (HDH) desalination system driven by an absorption-compression heat pump cycle (ACHPC) is carried out in this paper. The proposed hybrid desalination system uses both heating capacity of the discharged brine as a waste heat for the ACHPC and mechanical power of the ACHPC for the HDH system. The system's performance is investigated under different optimal design modes, using genetic algorithm (GA) as the most robust tool for optimization. A steady-state mathematical model based on the mass, energy, exergy, and exergoeconomic balance equations for components of the proposed system is developed and the predicted results are validated... 

Cooling production at different temperature levels for various applications has been highlighted in recent years since the produced cooling capacity must be used for different applications to meet all subjects’ demands. For this purpose, a novel dual-loop bi-evaporator vapor compression refrigeration cycle is proposed to meet these demands for freezing and air-conditioning applications which can be employed in building sectors. Later, ejector expander is used in place of the expansion valve in the proposed refrigeration system to enhance the performance of this basic system based on the thermodynamics and thermoeconomics viewpoints. Four working fluids of R717, R290, R600a, and R134a are... 

Hybrid renewable energy heat sources provide more sustainable energy resources with high maintenance for high-efficient power plants. Multigeneration systems driven by a hybrid renewable source are proved as cutting-edge technologies in recent studies. In this study, a novel multigeneration system driven by a hybrid biogas-geothermal heat source is proposed and simulated. To demonstrate the feasibility of the proposed multigeneration system, first and second laws analysis are employed as the most effective tools for performance assessment of the systems. It is found that the proposed multigeneration system can produce overall heating capacity, overall cooling capacity, net output power,... 

This paper deals with reconstruction of conventional combined cooling and power (CCCP) cycle for producing simultaneous power and cooling outputs for triple applications of freezing, refrigeration and air-conditioning. The proposed systems are integrated from organic Rankine cycles (ORCs) and an ejector refrigeration cycle (ERC). Single- and multi-objective optimisations of the proposed systems are conducted from energy, exergy and exergoeconomic viewpoints, using genetic algorithm (GA). The results of optimisation revealed that the thermal efficiency of the basic triple-evaporator CCP (B-TECCP) and regenerative TECCP (R-TECCP) systems can be improved by 7.48% and 6.23%, respectively,... 

Hybridization of biogas and geothermal energies for power plants can present a promising way to resolve drawbacks of each individual heat source from economic viewpoint, especially when low-temperature geothermal heat source is posited. Concerning this aspect of hybrid renewable heat sources, a novel hybrid biogas-geothermal multigeneration system was proposed in the first part of our study, which was modeled under privilege of thermodynamic laws. In continuation of our previous study, the current study is performed to investigate economic, environmental, and enviroeconomical aspects of the introduced system. Furthermore, single and multi-criteria optimizations of this integrated system are... 

Extraction of thermal heat from a salinity-gradient solar pond (SGSP) as a way of accumulating solar energy, stockpiling and taking merit of it for medium and low temperature demands is presented as an interesting topic in recent decades. This reliable supply of heat can be used for low-temperature refrigeration systems to yield cooling load for residential applications. For this purpose, theoretical investigation of ejector refrigeration cycle (ERC) driven by a SGSP is carried out to produce cooling output. Also, thermoelectric generator (TEG) is used as a potential device replacing condenser of the ERC for the sake of bolstering performance of the fundamental system by producing power,... 

Water shortage issues are growing through the globe at higher rate than population growth. On the bright side, various methods are devised to capture energy from renewable energy or waste heat from different sectors. Among all inspected approaches, waste heat capturing through cooling process of the wind turbines' generators for desalination at small scale is paid less attention. However, in large wind farms, the scale of this dissipated thermal heat becomes appreciable which can drive several desalination units. Due to the above-pointed facts, the waste heat of a wind turbine with nominal capacity of 7358 kW and height of 24 m for desalinating seawater is inspected here, using a...