Article
Thermodynamics
Mohammad Hassan Khanjanpour, Mohammad Rahnama, Akbar A. Javadi, Mohammad Akrami, Ali Reza Tavakolpour-Saleh, Masoud Iranmanesh
Summary: In this study, a gamma-type MDT Stirling engine prototype is manufactured, evaluated, and structurally optimized. An inexpensive mathematical evaluation based on FDT approach led to the determination of the optimal swept volume ratio under 450K temperature difference. Experimental results showed good agreement with the theoretical approach, validating its effectiveness in optimizing MTD Stirling engines.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Haoran Xu, Lingen Chen, Yanlin Ge, Huijun Feng
Summary: This paper utilizes finite time thermodynamics to analyze the Stirling heat engine and performs multi-objective optimization of the heat engine cycle using NSGA-II. The optimization of temperature ratio and volume compression ratio allows for a better balance among the four optimization objectives.
Article
Physics, Multidisciplinary
S. Hamedani Raja, S. Maniscalco, G. S. Paraoanu, J. P. Pekola, N. Lo Gullo
Summary: In this study, the thermodynamic performance of a finite-time non-regenerative quantum Stirling-like cycle as a heat engine is investigated. It is found that the real-time dynamics of the driven open quantum system significantly affect the cycle's performance, with the efficiency depending on different time scales and compression/expansion speeds asymmetrically. Additionally, optimizing quantum heat engines may offer new freedom, where real-time endpoints of compression/expansion processes play a crucial role in achieving maximum output power and efficiency.
NEW JOURNAL OF PHYSICS
(2021)
Article
Thermodynamics
Ermerson F. de Moura, Izabela B. Henriques, Guilherme B. Ribeiro
Summary: In recent years, there has been an increased interest in space exploration, particularly in deep space missions, by space agencies and private companies. These missions require high energy levels, leading to the need for more efficient and compact energy conversion systems. This study developed a finite-time thermodynamic model and exergy analysis of a Stirling cycle for nuclear space power generation to address these challenges.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2022)
Article
Thermodynamics
Yanlin Ge, Heng Wu, Lingen Chen, Huijun Feng, Zhihui Xie
Summary: A more practical irreversible Atkinson cycle model is established by combining the finite piston speed thermodynamics and finite time thermodynamics and considering the irreversible losses caused by heat transfer, friction, finite piston speed, and internal irreversibility. By selecting performance parameters such as the ecological coefficient of performance, thermal efficiency, power output, and ecological function, and design parameters such as piston speed ratio and finite piston speed, the relationships among them are obtained, and the influences of finite piston speed and piston speed ratio on the performance parameters are presented. The research shows the importance of considering different piston speeds in each process and provides guidance for practical design.
Article
Energy & Fuels
Fatemeh Ahadi, Mohammad Azadi, Mojtaba Biglari, Seyed Navid Madani
Summary: The modern Stirling engine is important for its high efficiency and versatility in using various heat sources, as well as its quiet operation and consistent working fluid. This article analyzed the performance of the Stirling engine using a non-ideal adiabatic thermodynamics model and compared it to experimental results. The impact of coating type and thickness on the regenerator was investigated, with a regression model used for sensitivity analysis.
Article
Thermodynamics
Thavamalar Kumaravelu, Syamimi Saadon, Abd Rahim Abu Talib
Summary: The Stirling engine has high theoretical efficiency and multi-fuel adaptability, but its performance is penalized when integrated with a low heat source. This paper focuses on enhancing engine performance through heat transfer, investigating the effects of different types of fins on efficiency through numerical analysis. The addition of rectangular fins led to the highest efficiency of 19.03% with improvements in heat transfer rate, efficiency, and power output.
Article
Physics, Multidisciplinary
Paul Fadler, Alexander Friedenberger, Eric Lutz
Summary: This article focuses on optimizing the performance of information engines that convert information about the state of a system into work. A generalized finite-time Carnot cycle for a quantum information engine is introduced and its power output is optimized under low dissipation conditions. A general formula for the efficiency at maximum power, valid for arbitrary working media, is derived. The optimal performance of a qubit information engine subjected to weak energy measurements is also investigated.
PHYSICAL REVIEW LETTERS
(2023)
Article
Thermodynamics
Ermerson F. de Moura, Izabela B. Henriques, Guilherme B. Ribeiro
Summary: With the advancement of the new space era, there is an increasing need for long-term missions beyond Earth's orbit, such as Mars and Moon exploration. These missions are more complex in terms of duration and energy demand. In this study, a thermodynamic model of a nuclear-powered Stirling cycle coupled with a dynamic engine model was developed to provide insights into the system performance. The results showed that the regenerator efficiency and compression ratio have significant effects on the engine efficiency. The best parameters yielded a system with a power output of 260.5 kW and a power density of 35.38 kg.kW(-1). This study serves as a theoretical guideline for the future design of nuclear-powered Stirling engines for space applications.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2022)
Article
Thermodynamics
Mohammad Amin Babazadeh, Mojtaba Babaelahi, Mahdi Saadatfar
Summary: This study focuses on using heat transfer fins to enhance energy absorption in the heater section of a solar Stirling engine, and proposes modifications and introduces unique heat transfer fins to increase the heat received by the working fluid. Thermal analysis shows that using these new fins significantly increases the power and efficiency of the system.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Heng Wu, Yanlin Ge, Lingen Chen, Huijun Feng
Summary: The study establishes an irreversible reciprocating Diesel cycle model by considering various irreversibilities, and analyzes the relationships among different parameters through numerical calculations. The results show that the curves of different characteristics exhibit distinct shapes, and both piston speed and piston speed ratio have significant impacts on the cycle performance.
Article
Physics, Multidisciplinary
Haoran Xu, Lingen Chen, Yanlin Ge, Huijun Feng
Summary: This paper combines the mechanical efficiency theory and finite time thermodynamic theory to optimize an irreversible Stirling heat-engine cycle. The results indicate that multi-objective optimization results are better when choosing appropriate decision-making strategies.
Article
Physics, Multidisciplinary
Monica Costea, Stoian Petrescu, Michel Feidt, Catalina Dobre, Bogdan Borcila
Summary: The study focused on the performance of an irreversible Carnot cycle engine, considering the effects of external and internal irreversibilities. An optimization method was provided to optimize the temperature of the cycle fluid, resulting in distinct maximums for thermal efficiency and power output, along with different behaviors of entropy generation.
Article
Physics, Fluids & Plasmas
Y. H. Chen, Jin-Fu Chen, Zhaoyu Fei, H. T. Quan
Summary: In this study, a microscopic theory of the Curzon-Ahlborn (CA) engine is formulated by adopting the method of stochastic differential equation of energy. This theory provides a microscopic interpretation of the assumptions made by Curzon and Ahlborn and also derives the explicit expression of the protocol associated with the maximum power. Analytical results of power and efficiency statistics for the Brownian CA engine are obtained based on this theory.
Article
Energy & Fuels
Donghan Geng, Jiedong Cui, Lijun Fan
Summary: Solar desalination systems powered by solar dish-Stirling engines show increased water productivity with increasing absorber temperature, with the optimal energy and exergy efficiency range between 1100 to 1300 K. The system's maximum water productivity point is found at a higher sink side temperature.
Article
Thermodynamics
Ehsan Boumari, Masoumeh Mojazi Amiri, Amirhosein Khadang, Heydar Maddah, Mohammad Hossein Ahmadi, Mohsen Sharifpur
Summary: The purpose of this study is to investigate the effects of Reynolds number, different volume fractions of aluminum oxide nanofluid, and different heat fluxes on heat transfer performance in a helical tube. The results show that increasing the volume fraction of aluminum oxide nanofluid and Reynolds number leads to an increase in the Nusselt number. Similarly, increasing the constant heat flux also increases the Nusselt number. Artificial neural networks were used to predict the Nusselt number successfully, with a correlation coefficient of 0.944416302.
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2023)
Article
Thermodynamics
Bahram Ghorbani, Milad Sadeghzadeh, Mohammad Hossein Ahmadi, Mohsen Sharifpur
Summary: This study presents a novel approach to cogenerate liquid carbon dioxide and liquefied natural gas using air for energy storage and production. The integration of mixed refrigeration cycle, liquid air cold energy recovery, carbon dioxide liquefaction cycle, and combined cooling and power cycle enhances the system's output performance. Solar parabolic trough collectors are used to assist power production. Sensitivity analysis demonstrates the effect of pressure in liquid air and outlet temperature of the solar collector exchanger on specific energy and exergy efficiency.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Energy & Fuels
Kai Yang, Tianhao Shi, Tingzhen Ming, Yongjia Wu, Yanhua Chen, Zhongyi Yu, Mohammad Hossein Ahmadi
Summary: A fabric air dispersion system (FADS) integrates air transmission and distribution, addressing issues of uneven air supply and surface condensation associated with traditional ventilation systems. The proposed simulation method overcomes challenges of mesh generation and accuracy, and examines the effects of different shapes and opening configurations on flow and heat transfer characteristics in fiber ducts. The findings show that temperature rise inside the duct is correlated with flow rate, with faster flow speeds resulting in higher temperatures.
Article
Chemistry, Physical
Mohammad Hassan Shahverdian, Saba Sedayevatan, Mohammadmehdi Hosseini, Ali Sohani, Ramtin Javadijam, Hoseyn Sayyaadi
Summary: In this study, an off-grid solar-geothermal cogeneration system was investigated and optimized using a comprehensive multi-objective optimization approach. The system is able to produce power by Kalina cycle, hydrogen by proton exchange membrane electrolyzer (PEMEC), and freshwater by a multi-effect desalination (MED) unit. The final results show that in its optimum condition, the system is able to produce 182.09 m3/day of fresh water, with an energy efficiency of 6.23%, a payback period of 5.19 years, and a levelized cost of electricity (LCOE) of 0.238 $.kWh-1.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Thermodynamics
Ali Sohani, Mohammad Hassan Shahverdian, Hoseyn Sayyaadi, Sandro Niz Nizetic, Mohammad Hossein Doranehgard
Summary: A hybrid photovoltaic-wind turbine driven system with H2 storage unit is proposed for a residential building complex, utilizing the emerging technology DEVAP cooling system to enhance performance. Dynamic multi-objective optimization is used to find the best design, and compared with conventional optimization without heat recovery. Energy, environmental, and economic aspects are considered as objective functions. Sensitivity analysis shows that the system performs best with an electrical load of 80-120% and an inflation rate of 1.20.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Energy & Fuels
Abdollah Mehrpanahi, Moslem Akbari Vakilabadi, Sadegh Nikbakht Naserabad, M. H. Ahmadi
Summary: This research examines the thermodynamic properties of a combined cycle power plant and analyzes the effect of various parameters on its performance. The results demonstrate that increasing certain parameters improves system performance and exergy efficiency. The study also identifies the optimal performance point of the heat recovery steam generator using genetic algorithm optimization.
ENERGY SCIENCE & ENGINEERING
(2023)
Article
Energy & Fuels
Arezoo Rezaei, Hamid Vatanparast, Mohammad Ahmadi, Abbas Shahrabadi
Summary: This research aims to investigate the effect of oil and asphaltene chemistry on the sensitivity of oil production toward ion-tuned water. The results show that asphaltene molecules have a lower affinity toward sulfate ions, while seawater enriched with magnesium and calcium ions can reduce interfacial tension. Furthermore, the study finds that calcium and magnesium have a stronger desorption effect on hydrocarbons. The experimental approach in this study can serve as a benchmark for screening suitable reservoir oil for water injection.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Article
Energy & Fuels
Reza Yousefzadeh, Mohammad Ahmadi
Summary: In this paper, a novel hybrid deep learning-based upscaling method is proposed to handle highly channelized and layered reservoir models. The proposed method combines the ConvLSTM network with the fast marching method (FMM) to obtain the dynamic response of the reservoir without the need for full-physics flow simulation. This data-driven approach can be trained once and used to upscale new realizations, providing an advantage over conventional simulation-based methods.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Article
Energy & Fuels
Abdorrahim Rezaeipour, Bahram Dabir, Mohammad Ahmadi
Summary: The upstream oil and gas industry has long used decline curve analysis to forecast oil flow rates, but it has limitations in handling irregular variations in oil well flow behavior. This study employs the Hidden Markov Model (HMM) for dynamic uncertainty quantification in oil well flow forecast and estimated ultimate recovery (EUR). By determining appropriate decline curves and their probabilities, the HMM approach addresses the subjectivity and lack of uncertainty quantification in decline curve analysis.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Article
Thermodynamics
Sadegh Nikbakht Naserabad, Moslem Akbari Vakilabadi, Mohammad Hossein Ahmadi
Summary: In this research, the performance of a micro-gas turbine combined heating and cooling plant coupled with a solar PV system in an office building in Iran is analyzed. The study examines the impact of renewable to fossil fuel share on system performance and economy. The results show that strategies without solar energy are not economically viable even with supportive incentives for renewable energies.
INTERNATIONAL JOURNAL OF LOW-CARBON TECHNOLOGIES
(2023)
Article
Energy & Fuels
Saeed Khezerloo-ye Aghdam, Alireza Kazemi, Mohammad Ahmadi
Summary: This research investigates the effect of clay particles' weight percentage, ionic strength, total dissolved solids, and injection rate on fine migration in sandstone reservoirs. It was found that low-salinity water enhances fine migration and increases oil recovery, but damages wells. The presence of medium concentrations of divalent cations leads to partial fine migration, while high concentrations prevent fine migration.
SPE RESERVOIR EVALUATION & ENGINEERING
(2023)
Article
Engineering, Petroleum
Reza Yousefzadeh, Amin Bemani, Alireza Kazemi, Mohammad Ahmadi
Summary: Scale precipitation in petroleum equipment is a significant problem that causes damages and reduces oil production. This study compares the performance of 10 different machine learning algorithms in predicting scale formation based on pH and ionic compositions. The K-nearest neighbors (KNN) and ensemble learning models were found to be the most accurate tools for solving the scale/no-scale classification problem. The sensitivity analysis showed that variations in Ca concentration had the highest impact on scale precipitation.
SPE PRODUCTION & OPERATIONS
(2023)
Article
Multidisciplinary Sciences
Saeed Khezerloo-ye Aghdam, Alireza Kazemi, Mohammad Ahmadi, Saeed Parvizi Ghale
Summary: This study analyzed the adsorption behavior of saponin on sandstone rocks. The adsorption behavior followed the Langmuir isotherm model and remained applicable at elevated temperatures. Particle size was found to affect the adsorption capacity, with smaller particles showing higher capacity. A thermodynamic model was developed to predict the adsorption behavior of saponin on sandstone rocks. Furthermore, saponin exhibited lower critical micelles concentration and adsorption tendency compared to other natural surfactants, making it a potential superior option for chemical enhanced oil recovery (EOR) applications.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2023)
Review
Energy & Fuels
Aveek Gupta, Ravinder Kumar, Ashish Maurya, Mohammad H. Ahmadi, Bulbul Ongar, Anara Yegzekova, Jeet Prakash Sharma, Sumit Kanchan, Sagar Shelare
Summary: This review focuses on the use of nanoparticles as fuel additives to improve the emission and performance characteristics of internal combustion engines. By comparing fuels blended with nanoparticles to fuels without nanoparticles, it is found that nanoparticles can enhance fuel atomization and engine performance. Graphene and ceria nanoparticles show significant improvement in performance, while alumina reduces hydrocarbon and carbon monoxide emissions but increases nitrogen oxides. Overall, nanoparticles can improve the thermophysical characteristics of fuels and enhance engine emission and performance.
ENERGY SCIENCE & ENGINEERING
(2023)
Article
Energy & Fuels
Reza Yousefzadeh, Mohammad Ahmadi
Summary: This study introduces a novel method for parameterizing permeability realizations using ConvLSTM layers to build a Variational Autoencoder. Experimental results show that this method outperforms the 3D convolutional VAE.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Cameron Bracken, Nathalie Voisin, Casey D. Burleyson, Allison M. Campbell, Z. Jason Hou, Daniel Broman
Summary: This study presents a methodology and dataset for examining compound wind and solar energy droughts, as well as the first standardized benchmark of energy droughts across the Continental United States (CONUS) for a 2020 infrastructure. The results show that compound wind and solar droughts have distinct spatial and temporal patterns across the CONUS, and the characteristics of energy droughts are regional. The study also finds that compound high load events occur more often during compound wind and solar droughts than expected.
Article
Green & Sustainable Science & Technology
Ning Zhang, Yanghao Yu, Jiawei Wu, Ershun Du, Shuming Zhang, Jinyu Xiao
Summary: This paper provides insights into the optimal configuration of CSP plants with different penetrations of wind power by proposing an unconstrained optimization model. The results suggest that large solar multiples and TES are preferred in order to maximize profit, especially when combined with high penetrations of wind and photovoltaic plants. Additionally, the study demonstrates the economy and feasibility of installing electric heaters (EH) in CSP plants, which show a linear correlation with the penetration of variable energy resources.
Article
Green & Sustainable Science & Technology
M. Szubel, K. Papis-Fraczek, S. Podlasek
Article
Green & Sustainable Science & Technology
J. Silva, J. C. Goncalves, C. Rocha, J. Vilaca, L. M. Madeira
Summary: This study investigated the methanation of CO2 in biogas and compared two different methanation reactors. The results showed that the cooled reactor without CO2 separation achieved a CO2 conversion rate of 91.8%, while the adiabatic reactors achieved conversion rates of 59.6% and 67.2%, resulting in an overall conversion rate of 93.0%. Economic analysis revealed negative net present worth values, indicating the need for government monetary incentives.
Article
Green & Sustainable Science & Technology
Yang Liu, Yonglan Xi, Xiaomei Ye, Yingpeng Zhang, Chengcheng Wang, Zhaoyan Jia, Chunhui Cao, Ting Han, Jing Du, Xiangping Kong, Zhongbing Chen
Summary: This study investigated the effect of using nanofiber membrane composites containing Prussian blue-like compound nanoparticles (PNPs) to relieve ammonia nitrogen inhibition of rural organic household waste during high-solid anaerobic digestion and increase methane production. The results showed that adding NMCs with 15% PNPs can lower the concentrations of volatile fatty acids and ammonia nitrogen, and increase methane yield.
Article
Green & Sustainable Science & Technology
Zhong Ge, Xiaodong Wang, Jian Li, Jian Xu, Jianbin Xie, Zhiyong Xie, Ruiqu Ma
Summary: This study evaluates the thermodynamic, exergy, and economic performance of a double-stage organic flash cycle (DOFC) using ten eco-friendly hydrofluoroolefins. The influences of key parameters on performance are analyzed, and the advantages of DOFC over single-stage type are quantified.
Article
Green & Sustainable Science & Technology
Nicolas Kirchner-Bossi, Fernando Porte-Agel
Summary: This study investigates the optimization of power density in wind farms and its sensitivity to the available area size. A novel genetic algorithm (PDGA) is introduced to optimize power density and turbine layout. The results show that the PDGA-driven solutions significantly reduce the levelized cost of energy (LCOE) compared to the default layout, and exhibit a convex relationship between area and LCOE or power density.
Article
Green & Sustainable Science & Technology
Chunxiao Zhang, Dongdong Li, Lin Wang, Qingpo Yang, Yutao Guo, Wei Zhang, Chao Shen, Jihong Pu
Summary: In this study, a novel reversible liquid-filled energy-saving window that effectively regulates indoor solar radiation heat gain is proposed. Experimental results show that this window can effectively reduce indoor temperature during both summer and winter seasons, while having minimal impact on indoor illuminance.
Article
Green & Sustainable Science & Technology
Alessandro L. Aguiar, Martinho Marta-Almeida, Mauro Cirano, Janini Pereira, Leticia Cotrim da Cunha
Summary: This study analyzed the Brazilian Equatorial Shelf using a high-resolution ocean model and found significant tidal variations in the area. Several hypothetical barrages were proposed with higher annual power generation than existing barrages. The study also evaluated the installation effort of these barrages.
Article
Green & Sustainable Science & Technology
Francesco Superchi, Nathan Giovannini, Antonis Moustakis, George Pechlivanoglou, Alessandro Bianchini
Summary: This study focuses on the optimization of a hybrid power station on the Tilos island in Greece, aiming to increase energy export and revenue by optimizing energy fluxes. Different scenarios are proposed to examine the impact of different agreements with the grid operator on the optimal solution.
Article
Green & Sustainable Science & Technology
Peimaneh Shirazi, Amirmohammad Behzadi, Pouria Ahmadi, Sasan Sadrizadeh
Summary: This research presents two novel energy production/storage/usage systems to reduce energy consumption and environmental effects in buildings. A biomass-fired model and a solar-driven system integrated with photovoltaic thermal (PVT) panels and a heat pump were designed and assessed. The results indicate that the solar-based system has an acceptable energy cost and the PVT-based system with a heat pump is environmentally superior. The biomass-fired system shows excellent efficiency.
Article
Green & Sustainable Science & Technology
Zihao Qi, Yingling Cai, Yunxiang Cui
Summary: This study aims to investigate the operational characteristics of the solar-ground source heat pump system (SGSHPS) in Shanghai under different operation modes. It concludes that tandem operation mode 1 is the optimal mode for winter operation in terms of energy efficiency.
Article
Green & Sustainable Science & Technology
L. Bartolucci, S. Cordiner, A. Di Carlo, A. Gallifuoco, P. Mele, V. Mulone
Summary: Spent coffee grounds are a valuable biogenic waste that can be used as a source of biofuels and valuable chemicals through pyrolysis and solvent extraction processes. The study found that heavy organic bio-oil derived from coffee grounds can be used as a carbon-rich biofuel, while solvent extraction can extract xantines and p-benzoquinone, which are important chemicals for various industries. The results highlight the promising potential of solvent extraction in improving the economic viability of coffee grounds pyrolysis-based biorefineries.
Article
Green & Sustainable Science & Technology
Luiza de Queiroz Correa, Diego Bagnis, Pedro Rabelo Melo Franco, Esly Ferreira da Costa Junior, Andrea Oliveira Souza da Costa
Summary: Building-integrated photovoltaics, especially organic solar technology, are important for reducing greenhouse gas emissions in the building sector. This study analyzed the performance of organic panels laminated in glass in a vertical installation in Latin America. Results showed that glass lamination and vertical orientation preserved the panels' performance and led to higher energy generation in winter.
Article
Green & Sustainable Science & Technology
Zhipei Hu, Shuo Jiang, Zhigao Sun, Jun Li
Summary: This study proposes innovative fin arrangements to enhance the thermal performance of latent heat storage units. Through optimization of fin distribution and prediction of transient melting behaviors, it is found that fin structures significantly influence heat transfer characteristics and melting behaviors.
