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organic-rankine-cycles
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Energy and exergy assessments of modified Organic Rankine Cycles (ORCs)
, Article Energy Reports ; Volume 1 , November , 2015 , Pages 1-7 ; 23524847 (ISSN) ; Aramoun, F ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
This paper presents a theoretical framework for the energy and exergy evaluation of a basic as well as three modified Organic Rankine Cycles (ORCs). The modified ORCs considered incorporating turbine bleeding, regeneration and both of them. The results demonstrate that evaporator has major contribution in the exergy destruction which is improved by increase in its pressure. The results confirm that the integrated ORC with turbine bleeding and regeneration has the highest thermal and exergy efficiencies (22.8% and 35.5%) and the lowest exergy loss (42.2 kW) due to decrease in cold utility demand and high power generation
A recent review of waste heat recovery by Organic Rankine Cycle
, Article Applied Thermal Engineering ; Volume 143 , 2018 , Pages 660-675 ; 13594311 (ISSN) ; Fazli, M ; Morad, M. R ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The increment of using fossil fuels has caused many perilous environmental problems such as acid precipitation, global climate change and air pollution. More than 50% of the energy that is used in the world is wasted as heat. Recovering the wasted heat could increase the system efficiency and lead to lower fuel consumption and CO2 production. Organic Rankine cycle (ORC) which is a reliable technology to efficiently convert low and medium temperature heat sources into electricity, has been known as a promising solution to recover the waste heat. There are numerous studies about ORC technology in a wide range of application and condition. The main objective of this paper is to presents a...
Performance analysis and multi-objective optimization of an organic Rankine cycle with binary zeotropic working fluid employing modified artificial bee colony algorithm
, Article Journal of Thermal Analysis and Calorimetry ; 2018 ; 13886150 (ISSN) ; Maghsoudi, P ; Shabani, B ; Gorgani, H. H ; Shabani, N ; Sharif University of Technology
Springer Netherlands
2018
Abstract
From a thermal point of view, zeotropic mixtures are likely to be more efficient than azeotropic fluids in low-temperature power cycles for reduction in exergy destruction occurring during heat absorption/rejection processes due to their suitable boiling characteristics. In this study, comprehensive energetic and exergetic analyses are mathematically performed for an organic Rankine cycle (ORC) system employing a potential binary zeotropic working fluid, namely R717/water. For this purpose, initially mass, energy, and exergy balance equations are derived. With regard to the similarity in molar mass of R717 (17.03 g mol−1) and water (18.01 g mol−1), there is no need to alter the size of the...
Combined desiccant-ejector cooling system assisted by organic rankine cycle for zero-power cooling and dehumidification
, Article International Conference on Climate Resilient Cities - Energy Efficiency and Renewables in the Digital Era 2019, CISBAT 2019, 4 September 2019 through 6 September 2019 ; Volume 1343, Issue 1 , 2019 ; 17426588 (ISSN) ; Rostamzadeh, H ; Khovalyg, D ; Scartezzini, J. L ; Smith, B ; Swiss Federal Office of Energy ; Sharif University of Technology
Institute of Physics Publishing
2019
Abstract
This study presents a novel set-up for desiccant-based cooling and dehumidification systems. In this cycle, a solid desiccant and conventional combined cooling and power (CCP) systems, based on the ejector refrigeration cycle (ERC) and the organic Rankine cycle (ORC), are integrated to provide dehumidification and cooling, simultaneously. The ERC is integrated with the ORC for devising a self-powered design which has not been done until now. The proposed integrated system is useful for replacing the peak electricity demand with the heat demand, decreasing the pressure on the power grid in humid areas. Dynamic hourly simulation of the proposed system as well as a conventional system were...
Performance analysis and multi-objective optimization of an organic Rankine cycle with binary zeotropic working fluid employing modified artificial bee colony algorithm
, Article Journal of Thermal Analysis and Calorimetry ; Volume 136, Issue 4 , 2019 , Pages 1645-1665 ; 13886150 (ISSN) ; Maghsoudi, P ; Shabani, B ; Gorgani, H. H ; Shabani, N ; Sharif University of Technology
Springer Netherlands
2019
Abstract
From a thermal point of view, zeotropic mixtures are likely to be more efficient than azeotropic fluids in low-temperature power cycles for reduction in exergy destruction occurring during heat absorption/rejection processes due to their suitable boiling characteristics. In this study, comprehensive energetic and exergetic analyses are mathematically performed for an organic Rankine cycle (ORC) system employing a potential binary zeotropic working fluid, namely R717/water. For this purpose, initially mass, energy, and exergy balance equations are derived. With regard to the similarity in molar mass of R717 (17.03 g mol −1 ) and water (18.01 g mol −1 ), there is no need to alter the size of...
An evaluation of wind turbine waste heat recovery using organic Rankine cycle
, Article Journal of Cleaner Production ; Volume 214 , 2019 , Pages 705-716 ; 09596526 (ISSN) ; Hajabdollahi, Z ; Hoghooghi, H ; Kim, K. C ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Wind turbine size has increased to megawatt capacity, and the related technologies and facilities have improved, including the cooling systems. Currently, all of the heat generated by wind turbine components is wasted to the environment. This study presents a conceptual design of a novel method for waste heat recovery of a wind turbine using an organic Rankine cycle (ORC). An organic Rankine cycle is implemented to the wind turbine as a part of the cooling system. The proposed system is thermodynamically modeled to evaluate the amount of recovered energy. Seven working fluids are chosen and investigated in the simulations to estimate the working fluid effect. The results revealed that the...
Techno-economic analysis of a modified concentrating photovoltaic/organic Rankine cycle system
, Article International Journal of Ambient Energy ; Volume 43, Issue 1 , 2022 , Pages 2026-2038 ; 01430750 (ISSN) ; Roshandel, R ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
The combination of concentrating photovoltaic (CPV) and organic Rankine cycle (ORC) systems not only leads to a reduction of photovoltaic (PV) operating temperature, but also leads to an additional electric power production. Increase in the temperature of the PV decreases its operating efficiency, while increases the ORC efficiency. Therefore, there is an optimum temperature in which the total electricity produced by the combined system will be maximum. In this study, a modified CPV/ORC system is simulated and the optimum operating temperature of the PV panel is determined for different PV efficiencies. The most striking result is that increase in the PV nominal efficiency will result in the...
Design of a Heat Exchanger in an Organic Rankine Cycle Used for Engine Waste Heat Recovery
, M.Sc. Thesis Sharif University of Technology ; Morad, Mohammad Reza (Supervisor)
Abstract
In this project a heat pipe heat exchanger is designed for using in an organic rankine cycle. The cycle parameter and heat exchanger parameter are optimized at the same time. The cycle is optimized in three scenario and the results are compared. In the first scenario the objective function is the net power output of the cycle, in the second scenario the objective function is the ratio of net power output and heat transfer area(POPA) and the objective function of third optimization is POPA and exergy destruction rate(EDR). With first scenario as base case, in second scenario POPA is increased 94% and in second scenario EDR and POPA are increased 9% and 75% respectively. The results show that...
Simulation and Techno–Economical Analysis of an Improved Integrated Concentrated Photovoltaic/Organic Rankine Cycle System
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
The combination of photovoltaic technology and Organic Rankine Cycle reduces the temperature of the solar panel and, on the other hand, generates separate electricity from excess heat. The reason for the use of the Organic Rankine Cycle is the low temperature of the heat source. It is not economical to use other cycles like steam Rankine cycle in low-temperature heat sources. To maximize the plant factor of the Organic Rankine cycle system, especially when there is not enough solar radiation, it is possible to utilize the flue gas heat recovery in office buildings and reduce the cost of electricity generation. In this project, the simulation of this system is carried out for the Energy...
Feasibility Analysis of Radial Outflow Turbine in Microturbine
, M.Sc. Thesis Sharif University of Technology ; Ghorbanian, Kaveh (Supervisor)
Abstract
It has been well documented over the years that axial and radial inflow turbines have traditionally been the solutions of choice for organic Rankine cycles. Recently, the advantages of radial outflow turbines in various operating conditions of the organic Rankine cycle have been highlighted. However, no research has been done on the use of this type of turbine in other cycles and for relatively high cycle pressure and temperature conditions. Further, there is no information on the design process of radial outflow turbines in the open literature. The purpose of this research is to compile a relatively accurate process of designing a radial outflow turbine and the feasibility of using it in a...
Energy and exergy evaluation of a new bi-evaporator electricity/cooling cogeneration system fueled by biogas
, Article Journal of Cleaner Production ; Volume 233 , 2019 , Pages 1494-1509 ; 09596526 (ISSN) ; Vajdi, M ; Rostamzadeh, H ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
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...
Investigation of the performance of modified organic Rankine cycles (ORCs) and modified trilateral flash cycles (TFCs) assisted by a solar pond
, Article Solar Energy ; Volume 182 , 2019 , Pages 361-381 ; 0038092X (ISSN) ; Akbari, A ; Khalilian, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Solar pond is a type of solar collector that stores solar energy in the form of heat. The solar pond can be used as a low-temperature heat source for electricity generation. In this paper, to find the most suitable power cycle for power generation from the solar pond, the performance of the Organic Rankine Cycle (ORC), Trilateral Flash Cycle (TFC) and their modified forms with an open feed liquid heater and an internal heat exchanger for different working fluids was investigated. Water was considered as the heat transfer fluid which transfers the stored heat from the solar pond to the working fluid of the cycle. The results indicate that in all cases, the energy and exergy efficiency of the...
Techno-economic analysis of a modified concentrating photovoltaic/organic Rankine cycle system
, Article International Journal of Ambient Energy ; 17 February , 2020 ; Roshandel, R ; Sharif University of Technology
Taylor and Francis Ltd
2020
Abstract
The combination of concentrating photovoltaic (CPV) and organic Rankine cycle (ORC) systems not only leads to a reduction of photovoltaic (PV) operating temperature, but also leads to an additional electric power production. Increase in the temperature of the PV decreases its operating efficiency, while increases the ORC efficiency. Therefore, there is an optimum temperature in which the total electricity produced by the combined system will be maximum. In this study, a modified CPV/ORC system is simulated and the optimum operating temperature of the PV panel is determined for different PV efficiencies. The most striking result is that increase in the PV nominal efficiency will result in the...
An integrated process configuration of solid oxide fuel/electrolyzer cells (SOFC-SOEC) and solar organic Rankine cycle (ORC) for cogeneration applications
, Article International Journal of Energy Research ; Volume 45, Issue 7 , 2021 , Pages 11018-11040 ; 0363907X (ISSN) ; Karimian Bahnamiri, F ; Mehrpooya, M ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
This research work presents a novel integrated structure for the cogeneration of electricity and renewable syngas. The base structure of the process is developed by solid oxide cells in which electricity is generated by the natural gas-fueled fuel cell unit, and renewable syngas is produced by the electrolyzer cell unit. Direct integration between fuel cell and electrolyzer cell units is established for optimal use of fuel cell off-gases. To improve system's sustainability, a solar power cycle, including solar collectors coupled with an organic Rankine cycle (ORC), is designed to provide renewable electricity for steam and CO2 co-electrolysis operation. 1D mathematical approaches are...
Evaluation of Energy Recovery by Development of Natural Gas Transmission Network Model
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
The development of natural gas supply systems and its transmission networks are vitally important to achieve a natural gas economy. Development and planning of natural gas transmission networks as multidisciplinary projects have crucial impact on the economy of gas-rich countries like Iran. The nvestment costs and operation expenses of pipeline networks are so large that even small improvements in system utilization and planning can involve substantial amounts of money. A large number of technological options exist for development in conversion, distribution levels and …, which cause various pathways for supplying natural gas. In addition there are many energy recovery technologies along...
Model for Optimal design of Energy Recovery System in Cement Plant
, M.Sc. Thesis Sharif University of Technology ; Sabouhi, Yadollah (Supervisor)
Abstract
The purpose of the present study is to develope an optimal model for analysis the impact of implementing a heat recovery system in a cement production line. For this goal, the energy reference system of a cement plant has been prepared, mass and energy balance sheets of the cement factory with dry production method, the characteristics of two high-energy streams have been identified in order to estimate the potential of heat recovery. Regarding the temperature range of the main hot streams, an appropriate cycle for generating electrical power from the lost heat, the Rankine cycle with organic fluid (ORC) has been formulated. The main question in the present project was how to relate the...
A Methodology for the Design of an Integration System for Water Capturing, Carbon Capture, and Heat Recovery from Flue Gas in Power Plants
, M.Sc. Thesis Sharif University of Technology ; Avami, Akram (Supervisor)
Abstract
This work presents a mathematical model for retrofitting the steam power plants in a refinery site. This problem is formulated as a mixed-integer nonlinear program (MINLP). Feasible retrofit alternatives suggested by experienced field engineers are investigated in sequence to examine the saving of those possible modifications. Furthermore, techno economic simulation of water and energy recovery systems from boiler flue gasses has been examined to obtain the optimal condition of these systems. For heat recovery, a systematic model for using organic Rankine cycle has been developed and results showed that toluene is the best possible working fluid in this case. Finally, water absorption cycle...
Development of Improved Conversion Energy System based on High Temperature Fuel Cells
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
Sustainable development is the basic aim of energy researchers. But common conversion technologies with respect to efficiency, fuel type and pollution of them, need basic operating improvement to reach sustainable development. Aim of this project is investigation of high temperature fuel cells as basic energy convertor. To improve performance of fuel cell system, four integration systemsare modeled and proposed. Using integrated systems in combined cooling, heat and power is another way of improving performance of systems, that is done in this project.
To improve system performance, the optimum operating values of these parameters is determined. In order to use four proposed system in...
To improve system performance, the optimum operating values of these parameters is determined. In order to use four proposed system in...
Experimental Study and Modeling of an Organic Rankine Cycle (Orc) Using Low-Temperature Systems
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor) ; Hajilouy Benisi, Ali (Supervisor)
Abstract
Increasing fossil fuel consumption has led to serious problems in energy supply and environmental issues such as global warming, air pollution, ozone depletion, and security issues. A strategy to improve energy consumption requires recycling wasted energy and preventing it from being released into the environment. A wide range of available heat sources such as heat dissipation in the transportation industry, solar heat, biomass and geothermal have low-temperature, which contain large amounts of energy but they do not have enough temperature to make them economically viable and cost-effective. Several applied technologies have been proposed to utilize these resources, among which the organic...
Analysis of Transition of A System from Third Generation to Fourth Generation and Prediction of Its Optimum Behavior
, M.Sc. Thesis Sharif University of Technology ; Saidi, Mohamed Hassan (Supervisor)
Abstract
The purpose of the current study is the thermodynamic, economic and environmental analysis of a cogeneration system capable of generating power, freshwater and/or air conditioning (AC) used in buildings. A photovoltaic-thermal system was used in conjunction with a concentrated reflector in order to generate power and heat. Photovoltaic cells and the cogeneration cycle turbine were tasked with generating electric power. In addition, a portion of the heat generated by the thermal collector was used to preheat the working fluid of the third-generation cogeneration cycle and another portion was used to produce freshwater. In order to provide the AC needed during summer, the cogeneration cycle...