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Evolutionary algorithm for multi-objective exergoeconomic optimization of biomass waste gasification combined heat and power system
, Article 2009 7th IEEE International Conference on Industrial Informatics, INDIN 2009, Cardiff, 23 June 2009 through 26 June 2009 ; 2009 , Pages 361-366 ; 19354576 (ISSN); 9781424437603 (ISBN) ; Farhanieh, B ; Marzi, H ; Javadzadegan, A ; Sharif University of Technology
2009
Abstract
This paper conducts research on Thermodynamic modeling of the Fluidized bed Gasification and Exergoeconomic evaluation to determine the total cost of a combined heat and power system with pressurized fluidized bed gasifier. The paper presents use of multi-objective evolutionary optimization for the system's total cost minimization and Exergetic efficiency maximization, and has been compared to conventional iterative optimization method. It shows that by evaluating with conventional iterative optimization, Exergetic efficiency of total system can reach to 56.09% while using multi-objective evolutionary optimization it is 53.32%. However the product cost achieved by evolutionary optimization...
Fabrication and characterization of TiO2 deposited black electroless Ni-P solar absorber
, Article Applied Surface Science ; Volume 496 , 2019 ; 01694332 (ISSN) ; Ghorbani, M ; Afshar, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Preparing a selective, efficient, and low-cost solar absorber is one of the main challenges in solar to thermal energy conversion. In this paper, black electroless Ni–P (ENi-P) solar absorber has been fabricated, and the effect of nanoporous TiO2 antireflection layer (ARL) on its optical and corrosion properties has been investigated. The optimum black coating was obtained by blackening in 9 M nitric acid solution at 50 °C for 40 s, in which a solar absorptance of 99.3% was achieved. Deposition of TiO2 ARL increased the solar absorptance of coating to 99.7% and addition of 0.8 g Pluronic F127 (F127) as pore former, further increased this value to 99.9% and solar-to-heat efficiency of the...
Effect of ZnO nanoparticles coating layers on top of ZnO nanowires for morphological, optical, and photovoltaic properties of dye-sensitized solar cells
, Article Micromachines ; Volume 10, Issue 12 , 2019 ; 2072666X (ISSN) ; Farooq, W. A ; Iftikhar Khan, M ; Niaz Akhtar, M ; Rehman, S. U ; Ahmad, N ; Khalid, M ; Atif, M ; AlMutairi, M. A ; Irfan, M ; Sharif University of Technology
MDPI AG
2019
Abstract
This paper reports on the synthesis of ZnO nanowires (NWs), as well asthe compound nanostructures of nanoparticles (NPs) and nanowires (NWs+NPs) with different coating layers of NPs on the top of NWs and their integration in dye-sensitized solar cells (DSSCs). In compound nanostructures, NWs offer direct electrical pathways for fast electron transfer, and the NPs of ZnOdispread and fill the interstices between the NWs of ZnO, offering a huge surface area for enough dye anchoring and promoting light harvesting. A significant photocurrent density of 2.64mA/cm2 and energy conversion efficiency of 1.43% was obtained with NWs-based DSSCs. The total solar-to-electric energy conversion efficiency...
Complex modal analysis and coupled electromechanical simulation of energy harvesting piezoelectric laminated beams
, Article Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science ; Volume 233, Issue 7 , 2019 , Pages 2526-2537 ; 09544062 (ISSN) ; Ahmadian, M. T ; Zohoor, H ; Sharif University of Technology
SAGE Publications Ltd
2019
Abstract
In this paper, coupled electromechanical behavior of a vibrational energy harvesting system composed of a unimorph piezoelectric laminated beam with a large attached tip mass is investigated. To achieve this goal, first the electromechanically coupled partial differential equations governing the lateral displacement and output voltage of the harvester are extracted through exploiting the Hamilton’s principle. Considering vibration damping due to mechanical to electrical energy conversion, a complex modal analysis is performed to extract the complex eigenfrequencies and eigenfunctions of the system. Furthermore, an exact analytical solution is presented for the system response to the harmonic...
Investigation and visualization of surfactant effect on flow pattern and performance of pulsating heat pipe
, Article Journal of Thermal Analysis and Calorimetry ; Volume 139, Issue 3 , 2020 , Pages 2099-2107 ; Kalan, K ; Vandadi, M ; Shafii, M. B ; Saidi, M. H ; Sharif University of Technology
Springer Netherlands
2020
Abstract
Pulsating heat pipes (PHPs) are one of the new devices used for cooling in several applications such as electronic and aerospace systems. Their low cost, effectiveness at various conditions, being equipped for passive energy conversion, and well distribution of temperature compared to conventional heat pipes are among the reasons of their popularity. To investigate the effect of surface tension of the working fluid on the behavior of PHPs, a copper heat pipe is fabricated with inner and outer diameters of 2 mm and 4 mm, respectively. Five different concentrations of cetrimonium bromide (C-Tab) surfactant are dissolved in water and are tested with a filling ratio of 50% (± 1%). A piece of...
Exergoeconomic optimization of a new trigeneration system driven by biogas for power, cooling, and freshwater production
, Article Energy Conversion and Management ; Volume 205 , 2020 ; Vajdi, M ; Rostamzadeh, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
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...
Self-powered wearable piezoelectric sensors based on polymer nanofiber-metal-organic framework nanoparticle composites for arterial pulse monitoring
, Article ACS Applied Nano Materials ; Volume 3, Issue 9 , August , 2020 , Pages 8742-8752 ; Hasanzadeh, M ; Simchi, A ; Sharif University of Technology
American Chemical Society
2020
Abstract
High-performance wearable electronic devices with the capability of converting mechanical force into electrical energy have been gaining increasing attention for biomedical monitoring applications. We present a novel wearable piezoelectric sensor based on a poly(vinylidene fluoride) (PVDF) nanofibrous membrane containing microporous zirconium-based metal-organic frameworks (MOFs) for arterial pulse monitoring. It is shown that the incorporation of 5 wt % of MOF greatly enhances the piezoelectric constant of the polymer fibrous mat by 3.4-fold without significant loss in its flexibility. The nanofibrous composite exhibits a peak-to-peak voltage of 600 mV under an applied force of 5 N, which...
A low cost Hydrokinetic Wells turbine system for oceanic surface waves energy harvesting
, Article Renewable Energy ; Volume 156 , 2020 , Pages 610-623 ; Abbaspour, M ; Taeibi Rahni, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
This paper provides a feasibility study on a low cost system called Hydrokinetic Wells turbine for surface wave energy conversion without using plenum chambers. The elimination of the plenum chamber and its complicated valve systems can reduce the expenses of wave energy conversion up to 23%.The feasibility process were done for high and low frequency conditions. For the low frequency waves, we offer the 300 rpm angular velocity as an optimum selection for further studies. For the high frequency condition a reliable analytical approach based on validated methods was developed. The analytical results indicate that a wells turbine with 60 cm diameter could produce up to 1600 Watts power in...
Efficiency improvement of solar stills through wettability alteration of the condensation surface: An experimental study
, Article Applied Energy ; Volume 268 , 2020 ; Soltani Goharrizi, A ; Ayatollahi, S ; Feilizadeh, M ; Dashti, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The condensation process is of great importance in many heat transfer devices in which a large amount of energy must be transferred. Furthermore, condensation is a crucial part of energy conversion and affects the energy efficiency of thermal desalination plants and solar stills. During the condensation process in solar stills, an essential part of the energy is transferred through the condensation surface to produce fresh water. Therefore, the condensation surface plays a significant role in the working efficiency of solar stills. The wettability of the condensation surface influences the condensation mechanism, which, in turn, affects the efficiency of solar stills. This study aims to...
Observability and estimation of transformer tap setting with minimal PMU placement
, Article IEEE Power and Energy Society 2008 General Meeting: Conversion and Delivery of Electrical Energy in the 21st Century, PES, Pittsburgh, PA, 20 July 2008 through 24 July 2008 ; 2008 ; 9781424419067 (ISBN) ; Hosseini, S. H ; Sharif University of Technology
2008
Abstract
One of the most important applications of phasor measurement units (PMUs) is power system state estimation. Some models have been proposed for including phasor measurements in the state estimation. But, all of these models have treated transformer tap settings (voltage transformer turns ratio and phase-shift transformer angle) as fixed parameters of the network. The accuracy of state estimation may decrease when a tap changes or the true value is unknown. In this paper, each transformer tap setting is added as a new state variable to the states vector, converting the linear PMU based state estimation to a nonlinear one. Also, the network observability is analyzed including the observability...
Concept of best energy transfer scenario and a true expression for power factor
, Article IEEE Power and Energy Society 2008 General Meeting: Conversion and Delivery of Electrical Energy in the 21st Century, PES, Pittsburgh, PA, 20 July 2008 through 24 July 2008 ; 2008 ; 9781424419067 (ISBN) ; Khajehoddin, S. A ; Bakhshai, A ; Sharif University of Technology
2008
Abstract
The best energy transfer scenario (BETS) is a situation under which the optimum transfer of power (or energy) from the electric utility to an electric power consumer is achieved. Such a scenario is important because it is used as a reference point to evaluate how efficient the load operates. The index of power factor (PF) is used to quantify such an efficiency. The closer the PF to unity corresponds to more efficient performance of the load. This paper is to show that the conventional definition of the BETS is inadequate and results in an unfair value for the PF unless the transmission line is perfect and lossless (which is an unrealistic condition). The paper also investigates an...
Optimum simultaneous clearing of energy and spinning reserve markets using cost/benefit analysis
, Article IEEE Power and Energy Society 2008 General Meeting: Conversion and Delivery of Electrical Energy in the 21st Century, PES, Pittsburgh, PA, 20 July 2008 through 24 July 2008 ; 2008 ; 9781424419067 (ISBN) ; Fotuhi Firuzabad, M ; Zareipour, H ; Sharif University of Technology
2008
Abstract
Considering the high level of interactions between energy and reserve markets, simultaneous clearing of these markets has been shown to provide more efficient solutions, than a sequential market clearing process. In addition, determining reserve requirements based on probabilistic approaches results in more economical efficiency, while maintaining an acceptable level of reliability, compared to deterministic approaches. This paper proposes a new method for clearing energy and spinning reserve markets simultaneously, while at the same time, spinning reserve requirements are determined based on a cost/benefit analysis as a probabilistic-based approach. This cost/benefit analysis considers both...
A compact mixer and DAC for implementation of a direct conversion OQPSK transmitter
, Article 2007 IEEE Region 10 Conference, TENCON 2007, Taipei, 30 October 2007 through 2 November 2007 ; 2007 ; 1424412722 (ISBN); 9781424412723 (ISBN) ; Mehrmanesh, S ; Zamanlooy, B ; Atarodi, M ; Sharif University of Technology
2007
Abstract
A compact low power circuit for implementation of a direct conversion OQPSK modulator is proposed. The circuit consists of a digital to analog converter, a low pass filter and an up-converter mixer. By embedding these three blocks, the circuit performance is enhanced and the total power consumption is reduced. The mixer is designed base on a Gilbert cell with on chip inductor loads. Instead of transconductance transistors of Gilbert cell, a fully deferential current mode DAC is used and proficiently a low pass filter is embedded between them and therefore the linearity of total system is improved. All of circuits are designed based on 0.18 μm CMOS technology with a single 1.8 volt power...
Design and simulation studies of hybrid power systems based on photovoltaic, wind, electrolyzer, and pem fuel cells
, Article Energies ; Volume 14, Issue 9 , 2021 ; 19961073 (ISSN) ; Alshukri, M. J ; Mikhaeel, L. M ; Al-Sawaf, N. N ; Nesrine, K ; Reddy, M. V ; Zaghib, K ; Sharif University of Technology
MDPI AG
2021
Abstract
In recent years, the need to reduce environmental impacts and increase flexibility in the energy sector has led to increased penetration of renewable energy sources and the shift from concentrated to decentralized generation. A fuel cell is an instrument that produces electricity by chemical reaction. Fuel cells are a promising technology for ultimate energy conversion and energy generation. We see that this system is integrated, where we find that the wind and photovoltaic energy system is complementary between them, because not all days are sunny, windy, or night, so we see that this system has higher reliability to provide continuous generation. At low load hours, PV and electrolysis...
Multi-objective optimization of regenerative ORC system integrated with thermoelectric generators for low-temperature waste heat recovery
, Article Energy Reports ; Volume 7 , 2021 , Pages 300-313 ; 23524847 (ISSN) ; Moosavi, A ; Sadrhosseini, H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Three novel geothermal-based organic Rankine cycle (ORC) systems are proposed to enhance the efficiency and for waste heat recovery purpose. The proposed systems are modeled based on a basic ORC system (concept 1), an ORC system with an internal heat exchanger (concept 2), and a regenerative ORC system (concept 3). Accordingly, two thermoelectric generators (TEG) are introduced into the systems to exploit the waste heat of the system. The condenser is replaced with a TEG unit while the other TEG unit is used to recover the waste heat of the reinjected geothermal fluid. A comprehensive numerical investigation is conducted to compare the proposed systems from the thermodynamic and...
Design and simulation studies of hybrid power systems based on photovoltaic, wind, electrolyzer, and pem fuel cells
, Article Energies ; Volume 14, Issue 9 , 2021 ; 19961073 (ISSN) ; Alshukri, M. J ; Mikhaeel, L. M ; Al-Sawaf, N. N ; Nesrine, K ; Reddy, M. V ; Zaghib, K ; Sharif University of Technology
MDPI AG
2021
Abstract
In recent years, the need to reduce environmental impacts and increase flexibility in the energy sector has led to increased penetration of renewable energy sources and the shift from concentrated to decentralized generation. A fuel cell is an instrument that produces electricity by chemical reaction. Fuel cells are a promising technology for ultimate energy conversion and energy generation. We see that this system is integrated, where we find that the wind and photovoltaic energy system is complementary between them, because not all days are sunny, windy, or night, so we see that this system has higher reliability to provide continuous generation. At low load hours, PV and electrolysis...
Multi-objective optimization of regenerative ORC system integrated with thermoelectric generators for low-temperature waste heat recovery
, Article Energy Reports ; Volume 7 , 2021 , Pages 300-313 ; 23524847 (ISSN) ; Moosavi, A ; Sadrhosseini, H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Three novel geothermal-based organic Rankine cycle (ORC) systems are proposed to enhance the efficiency and for waste heat recovery purpose. The proposed systems are modeled based on a basic ORC system (concept 1), an ORC system with an internal heat exchanger (concept 2), and a regenerative ORC system (concept 3). Accordingly, two thermoelectric generators (TEG) are introduced into the systems to exploit the waste heat of the system. The condenser is replaced with a TEG unit while the other TEG unit is used to recover the waste heat of the reinjected geothermal fluid. A comprehensive numerical investigation is conducted to compare the proposed systems from the thermodynamic and...
Coefficient of performance of mono-and multi-crystalline silicon photovoltaic panels
, Article Solar World Congress 2005: Bringing Water to the World, Including 34th ASES Annual Conference and 30th National Passive Solar Conference, Orlando, FL, 6 August 2005 through 12 August 2005 ; Volume 2 , 2005 , Pages 1045-1050 ; 9781622762637 (ISBN) ; Zamzamian, K ; Sharif University of Technology
2005
Abstract
The coefficient of performance (COP) of a photovoltaic panel or module is defined as the ratio of the total electrical energy produced by the panel during its life to the total energy spent for its manufacture. All processes involved for the manufacture of photovoltaic panels were considered and the energy spent per unit mass of the final product during each process was determined. The total electrical energy spent for the manufacture of a photovoltaic module of 1×0.5 m dimensions, employing 340 micron wafers, with the net wafer area of 0.36 m2, was then determined. Monocrystalline and multicrystalline silicon cells were employed. It was found that for the manufacture of the PV module...
2D MXene nanocomposites: electrochemical and biomedical applications
, Article Environmental Science: Nano ; Volume 9, Issue 11 , 2022 , Pages 4038-4068 ; 20518153 (ISSN) ; Nourmohammadi Khiarak, B ; Tao, R ; Wang, Z ; Ahmadi, S ; Hassanpour, M ; Rabiee, M ; Saeb, M. R ; Lima, E. C ; Rabiee, N ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
In recent years, key questions about the interaction of 2D MXene nanomaterials in electrochemical and biomedical applications have been raised. Most research has focused on clarifying the exclusive properties of the materials; however, only limited reports have described the biomedical applications of 2D nanomaterials. 2D MXenes are monolayer atomic nanosheets resulting from MAX phase ceramics. The hydrophilic properties, metallic conductivity, stability, and exclusive physiochemical performances make them promising materials for electrochemical and biomedical applications, including CO2 reduction, H2 evolution, energy conversion and storage, supercapacitors, stimuli-responsive drug delivery...
Details study on the kinematic characteristics of manta ray section in flapping motion and exploring its application in wave glider propulsion system
, Article Sustainable Energy Technologies and Assessments ; Volume 53 , 2022 ; 22131388 (ISSN) ; Safari, H ; Darbandi, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
It has always been a human challenge to inspire natural configurations and phenomena and benefit from their merits in improving the performances of man-made proposed aero/hydro vehicles. For example, the manta rays are known for their great swimming performances. To design and fabricate an underwater robot based on the manta ray geometry and its kinematic characteristics, it is important to initially study its hydrodynamic behavior and possibly arrive at some key design parameters, which can remarkably help to figure out an optimum geometry with high swimming performances. The main objective of this study is to focus on the merits of gliding motion inspired by the manta ray fish considering...