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Exergoenvironmental and exergoeconomic modelling and assessment in the complex energy systems
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 41, Issue 3 , 2022 , Pages 989-1002 ; 10219986 (ISSN) ; Choubanpisheh, S ; Talebi, S ; Khajehpour, H ; Sharif University of Technology
Iranian Institute of Research and Development in Chemical Industries
2022
Abstract
Traditionally energy systems were analyzed technically, but current environmental issues and considerations have put new constraints on the planning and managing of energy systems. Such an exergoeconomic and exergoenvironmental analysis were born. This analysis is aimed to describe the necessity and application of a new concept in environmental liability accounting based on physical quantities to overcome the weaknesses of the developed allocation methods and the internalization of external environmental damages. The proposed method is modified in environmental analysis to consider the effect of non-energy flows on a macro-surface energy system. As a case study, this method is tuned for a...
Novel dual-loop bi-evaporator vapor compression refrigeration cycles for freezing and air-conditioning applications
, Article Applied Thermal Engineering ; Volume 138 , 25 June , 2018 , Pages 563-582 ; 13594311 (ISSN) ; Rostamzadeh, J ; Matin, P. S ; Ghaebi, H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
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...
Performance assessment and optimization of a humidification dehumidification (HDH) system driven by absorption-compression heat pump cycle
, Article Desalination ; Volume 447 , 2018 , Pages 84-101 ; 00119164 (ISSN) ; Shekari Namin, A ; Ghaebi, H ; Amidpour, M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
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...
Thermodynamic and thermoeconomic analysis and optimization of a novel dual-loop power/refrigeration cycle
, Article Applied Thermal Engineering ; Volume 138 , 25 June , 2018 , Pages 1-17 ; 13594311 (ISSN) ; Ghaebi, H ; Vosoughi, S ; Jannatkhah, J ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
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.,...
Exergoeconomic optimisation of basic and regenerative triple-evaporator combined power and refrigeration cycles
, Article International Journal of Exergy ; Volume 26, Issue 1-2 , 2018 , Pages 186-225 ; 17428297 (ISSN) ; Mostoufi, K ; Ebadollahi, M ; Ghaebi, H ; Amidpour, M ; Sharif University of Technology
Inderscience Enterprises Ltd
2018
Abstract
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,...
Thermodynamic analysis of a novel combined power and refrigeration cycle comprising of EKalina and ejector refrigeration cycles
, Article International Journal of Refrigeration ; Volume 104 , 2019 , Pages 291-301 ; 01407007 (ISSN) ; Faegh, M ; Shafii, M. B ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
A novel combined power and refrigeration cycle is introduced and analyzed from the thermodynamic standpoint. The proposed cycle is an integration of a Kalina cycle equipped with an ejector (EKalina) and an ejector refrigeration cycle (ERC). In order to enhance the overall cycle performance, the possibility of employing two-phase ejectors in combined power and refrigeration cycles is studied. A parametric analysis is conducted to investigate the effects of the key thermodynamic parameters namely turbine inlet pressure, split ratio, basic ammonia concentration, heat source and evaporator temperatures on the cycle performance. The developed model is also verified with available data and it is...
An updated review of the performance of nanofluid-based photovoltaic thermal systems from energy, exergy, economic, and environmental (4E) approaches
, Article Journal of Cleaner Production ; 2020 ; Taheri, A ; Farzanehnia, A ; Passandideh fard, M ; Sardarabadi, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
One of the most prominent hybrid solar devices is the photovoltaic thermal system (PVTS), which is able to provide simultaneous electricity and thermal energy. The thermal energy is the heat absorbed by the photovoltaic (PV) module and transferred to the attached thermal collector and finally to the heat transfer fluid. Utilizing a proper heat transfer fluid is an effective means to increase in obtained thermal and electrical powers and enhance PV thermal management. Over the past decade, employing nanofluids thanks to their superior thermophysical properties became a proved strategy to improve the efficiency of the PVTS. This paper covers cutting-edge researches on nanofluid-based PVTS via...
Thermodynamic analysis of combustion processes and pollutants emission using nonlinear optimization approach
, Article Asia-Pacific Journal of Chemical Engineering ; Volume 7, Issue 1 , AUG , 2012 , Pages 80-85 ; 19322135 (ISSN) ; Zolfaghari Sharak, A ; Zolfaghari Shahrak, A ; Sharif University of Technology
2012
Abstract
Mathematical formulation and modeling of combustion processes is an important tool in the understanding of this phenomenon. Determination of equilibrium temperature and composition is often the first stage in calculation of combustion characteristics. There are number of different techniques for simulation of combustion process. In this study a basic model has been developed based on the minimization of Gibb's free energy to simulate the combustion processes. A nonlinear mathematical optimization has been developed based on Lagrange multipliers and solved using Quasi-Newton method written in MathCAD environment. The effect of various parameters such as initial temperature, pressure, and...
Supercritical gasification of biomass: Thermodynamics analysis with Gibbs free energy minimization
, Article Energy Sources, Part A: Recovery, Utilization and Environmental Effects ; Volume 34, Issue 2 , Dec , 2011 , Pages 163-176 ; 15567036 (ISSN) ; Pazuki, G. R ; Vossoughi, M ; Saboohi, Y ; Hashemi, N ; Sharif University of Technology
2011
Abstract
Gasification of biomass in supercritical water is a successful technology for hydrogen production especially by using wet biomass. The whole process, from feeding to purification of hydrogen, consists of a lot of equipment, such as pumps, heat exchangers, heaters, reactors, etc. Because the main reactions take place in the gasification reactor, the gasifier is the most important equipment of the process. In this article, a thermodynamic model, including chemical equilibrium in the reactor that is based on Gibbs free energy minimization, is developed to estimate equilibrium composition for gasification of biomass in supercritical water for hydrogen production. For this analysis, we use three...
Bonding, structural and thermodynamic analysis of dissociative adsorption of H3O+ ion onto calcite (10 1 ¯ 4) surface: CPMD and DFT calculations
, Article Journal of Molecular Modeling ; Volume 23, Issue 12 , 2017 ; 16102940 (ISSN) ; Koleini, M. M ; Sharif University of Technology
Abstract
We used density functional theory (DFT) and Car-Parrinello molecular dynamics (CPMD) simulation to investigate the adsorption and bond formation of hydronium ion (H3O+) onto a (10 1 ¯ 4) calcite surface. For surface coverage of 25% to 100%, the nature of H3O+ interaction was explored through electron density and energetics in the context of bond critical points. The adsorbate–adsorbent structure was studied by simulation of pair correlation function. The results revealed that dissociation into water molecule(s) and proton(s) complements H3O+ ion(s) adsorbtion. The H2O molecule adsorbs onto the surface via its O atom, and interacts with surface calcium in a closed-shell mode; the H+ ion makes...
Removal of benzoic acid from industrial wastewater using metal organic frameworks: equilibrium, kinetic and thermodynamic study
, Article Journal of Porous Materials ; Volume 24, Issue 1 , 2017 , Pages 165-178 ; 13802224 (ISSN) ; Safekordi, A. A ; Khorasheh, F ; Sharif University of Technology
Springer New York LLC
2017
Abstract
In this work, the adsorption of benzoic acid (BA) over metal organic framework of chromium-benzenedicarboxylates (MIL-101) is reported for the first time. The influences of pH, contact time, initial concentration, and temperature of BA solution on the adsorption behavior were investigated. The Langmuir adsorption isotherm was adequate to represent the experimental data (R2 > 0.99) and the adsorption kinetics was well-represented by a pseudo-second order kinetic model (R2 > 0.96). The zeta potential of MIL-101 decreased with increasing pH confirming the importance of electrostatic interactions between MIL-101 and BA as well as the importance of the large pore volume (1.32 m3/g) and large...
Thermodynamic assessment and multi-objective optimization of performance of irreversible dual-miller cycle
, Article Energies ; Volume 12, Issue 20 , 2019 ; 19961073 (ISSN) ; Ahmadi, M. H ; Pourkiaei, S. M ; Pourfayaz, F ; Mosavi, A ; Feidt, M ; Shamshirband, S ; Sharif University of Technology
MDPI AG
2019
Abstract
In this study, a new series of assessments and evaluations of the Dual-Miller cycle is performed. Furthermore, the specified output power and the thermal performance associated with the engine are determined. Besides, multi-objective optimization of thermal efficiency, ecological coefficient of performance (ECOP) and ecological function (Eun) by means of NSGA-II technique and thermodynamic analysis are presented. The Pareto optimal frontier obtaining the best optimum solution is identified by fuzzy Bellman-Zadeh, Linear Programming Technique for Multidimensional Analysis of Preference (LINMAP), and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) decision-making...
Proposal and assessment of a new geothermal-based multigeneration system for cooling, heating, power, and hydrogen production, using LNG cold energy recovery
, Article Renewable Energy ; Volume 135 , 2019 , Pages 66-87 ; 09601481 (ISSN) ; Rostamzadeh, H ; Zamani Pedram, M ; Ghaebi, H ; Amidpour, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Multigeneration systems (MGSs) driven by renewable sources are proved as cutting-edge technologies for multiple productions purposes to curb greenhouse gas emissions. With this regard, a novel geothermal-based MGS is proposed to produce multiple commodities of cooling, heating, power, and hydrogen, simultaneously, using liquefied natural gas (LNG) as cold energy recovery. The system is composed of an organic Rankine cycle (ORC), an ejector refrigeration cycle (ERC), an LNG power generation system, and a proton exchange membrane (PEM) electrolyzer system. To demonstrate the feasibility of the proposed MGS, energy, exergy, and exergoeconomic analysis are employed as the most effective tools...
Freshwater and cooling production via integration of an ethane ejector expander transcritical refrigeration cycle and a humidification-dehumidification unit
, Article Desalination ; Volume 477 , 2020 ; Vajdi, M ; Rostamzadeh, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
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...
Numerical investigation and parametric analysis of a photovoltaic thermal system integrated with phase change material
, Article Applied Energy ; Volume 238 , 2019 , Pages 734-746 ; 03062619 (ISSN) ; Salari, A ; Hakkaki Fard, A ; Ma, T ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this paper, a comprehensive three-dimensional model of photovoltaic thermal system integrated with phase change material (PVT/PCM) is developed and simulated. The effect of some key parameters using parametric analysis on performance of PVT/PCM system with water as working fluid is investigated. Parameters considered in this study include the properties of PCM (i.e. melting temperature, enthalpy of fusion and thermal conductivity), solar radiation and mass flow rate. The parametric analysis ranges are selected according to the properties of the most of available PCMs on the market, which shows the practical application of the numerical research. Furthermore, a three-dimensional model of...
Performance enhancement of waste heat extraction from generator of a wind turbine for freshwater production via employing various nanofluids
, Article Desalination ; Volume 478 , 2020 ; Rostami, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
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...