Article
Thermodynamics
Moh'd Al-Nimr, Saud Khashan, Hashem Al-Oqla
Summary: This paper demonstrates the technical feasibility of a novel hybrid Stirling Engine, coupled with inserted pyroelectric generators in its thermal regenerator, to produce extra power through the pyroelectric effect and increase engine performance.
Article
Thermodynamics
Pengfan Chen, Geyu Zhong, Yafeng Niu, Yingwen Liu
Summary: In this paper, a TD-Sage model is proposed for a beta-type free piston Stirling engine, and the performance of the engine is improved using the response surface methodology and desirability approach. The optimal design parameters and maximum output power are obtained through the analysis of factors and available energy loss analysis.
Article
Thermodynamics
Brayden T. York, Brendan D. MacDonald
Summary: This study used numerical methods to investigate the impact of misalignment and spacing on pressure losses in stainless steel wire mesh regenerators, developing a new friction factor correlation equation to include the effect of wire misalignment. The findings suggest that a perfectly aligned regenerator could result in a 38%-45% decrease in pressure losses, and that pressure loss reductions due to spacing are dependent on misalignment.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Energy & Fuels
Fatih Aksoy, Hamit Solmaz, Muhammed Arslan, Emre Yilmaz, Duygu Ipci, Alper Calam
Summary: This study examined the effects of a regenerator on the engine performance of a beta type Stirling engine. Stainless steel wire was used as the regenerator material in experiments, leading to a 5.97% increase in engine power and a 4% increase in engine torque when the regenerator was used.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2021)
Article
Thermodynamics
Shu-Han Hsu, Yen-Ting Li
Summary: This study experimentally observes the amplitude saturation process of spontaneous pressure oscillations in the thermoacoustic Stirling engine and finds that the nonlinear effects of the flow resistance of the stacked-screen regenerators decrease the amplitude of sound pressure oscillations with increasing Reynolds number. The measured stability limits agree with the theoretical calculations by adjusting r0.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2023)
Article
Energy & Fuels
Houda Hachem, Ramla Gheith, Fethi Aloui
Summary: Research on Stirling engines focuses on optimizing working parameters and studying the influence of gas qualities on power and efficiency. Different operating and geometric parameters were explored to identify optimal conditions for higher output power. Specific gas characteristics can have a significant impact on the performance of the engine.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Energy & Fuels
Mohammad Sheykhi, Mahmood Mehregan
Summary: In this paper, a novel adiabatic model (irreversible adiabatic) is proposed for the Ground Power Unit Stirling engine, which has higher accuracy than previous models. The effects of important parameters such as regenerator length, regenerator porosity, engine rotational speed, and pressure on the engine performance are investigated and optimal conditions of these parameters are provided for three different operating pressures. The engine modeling is conducted using the Runge-Kutta method and the genetic algorithm technique is used for optimization. The results show good agreement with experimental data in terms of power output and thermal efficiency. It is recommended to use short regenerators for proper thermal efficiency and high porosity coefficient at high rotational speeds.
Article
Thermodynamics
Meng Liu, Bilin Zhang, Dongtai Han, Xueping Du, Huanguang Wang
Summary: This study investigates the heat transfer and flow characteristics of the parallel-plate regenerator (PPR), a critical component of the Stirling engine. It is found that axial heat conduction reduces regenerative effectiveness, and higher thermal conductivity of the plate leads to lower effectiveness. Additionally, larger plate thickness and smaller plate length increase axial heat conduction loss. Comparative experiments with wire mesh regenerator reveal that PPR has better flow characteristics and lower friction coefficient. By comparing the overall performances using a comprehensive index, it is concluded that PPR has better working performance. The adverse effect of axial heat conduction on PPR is mitigated by segmenting the regenerator, resulting in a 20% increase in regenerative effectiveness with an acceptable increase in pressure drop.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Meng Liu, Bilin Zhang, Keqing Zheng, Xueping Du, Huanguang Wang
Summary: The research investigates the application of parallel-plate regenerator in Stirling engines and its influencing factors, finding that axial heat conduction has a detrimental effect on regenerative effectiveness. It is also observed that the working frequency and thermal properties of the working fluids have a comprehensive impact on regenerative effectiveness.
INTERNATIONAL JOURNAL OF GREEN ENERGY
(2022)
Article
Green & Sustainable Science & Technology
Moh'd Al-Nimr, Saud A. Khashan, Hashem Al-Oqla
Summary: This paper presents three novel techniques to enhance Stirling engines (SE). The use of Phase-Change Material (PCM) regenerators instead of conventional regenerators improves the performance of both the regenerator and the engine. Replacing the plate receiver of a Solar-Dish Stirling engine (SDSE) with a glass receiver increases direct radiation absorption and reduces energy losses. Coupling an SDSE system with a PCM Thermal Storage Reservoir (PCMTSR) allows for the storage and extraction of rejected heat energy during the day and night, utilizing either ambient air or geothermal water for night-time engine cooling. Theoretical models evaluate the impact of these modifications on SE performance.
Article
Thermodynamics
Hang-Suin Yang, Muhammad Aon Ali, Karumudi Venkata Ravi Teja, Yi-Feng Yen
Summary: The study focuses on optimizing the design of a kW-class beta-type Stirling engine with a rhombic drive mechanism for a concentrated solar power system, validating the simulation results with experimental data. The research demonstrates an increase in maximum shaft power of the prototype engine to 1503 W and improvements in thermal efficiency to 13.5% and mechanical efficiency to 94.3% can be achieved.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
John Dyreby, Justin Shumaker, Kristin E. Schaefer, John Corey, James J. Carroll, Christopher J. Chiara, Gregory Nellis
Summary: Currently, power systems are limited by the source and energy density of chemical fuels, leading to the development of nuclear energy sources. Nuclear isomers have a significantly higher energy density than chemical fuels and can be transformed to release energy. Switched nuclear isomer (SNI) materials provide abundant energy, but pose challenges in power conversion. This study explores the coupling of an SNI heat source to a kinematic Stirling engine and demonstrates its potential in achieving high conversion efficiency, high power density, and inherent modulation capability.
APPLIED THERMAL ENGINEERING
(2024)
Article
Chemistry, Physical
Humayun Arif, Aqueel Shah, Tahir Abdul Hussain Ratlamwala, Khurram Kamal, Maqsood Ahmed Khan
Summary: Population explosion, industrialization, and urbanization have increased global energy requirements, prompting the search for simple and cost-effective energy solutions. The addition of Shape Memory Alloy NiTiNOL to the Stirling engine has shown promising results in improving engine efficiency. The research focuses on changing the base plate material of the modified Stirnol engine and assessing its performance with the integration of a NiTiNOL spring.
Article
Thermodynamics
Minjie Yu, Chunyu Shi, Zhichun Liu, Wei Liu
Summary: This paper aims to design and optimize a novel annular constructal bifurcation regenerator to reduce the flow and axial heat conduction losses in traditional porous regenerators. Geometric parameters and regenerator performance were analyzed using numerical simulations and response surface methodology. Multi-objective optimization was conducted to minimize flow resistance and maximize heat transfer rate. The results show that the constructal bifurcation regenerator has high comprehensive performance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
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
Chemistry, Physical
V. Edwin Geo, C. Prabhu, S. Thiyagarajan, T. Maiyalagan, Fethi Aloui
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2020)
Article
Energy & Fuels
V. EdwinGeo, Guillaume Fol, Fethi Aloui, S. Thiyagarajan, M. Jerome Stanley, Ankit Sonthalia, Kathirvel Brindhadevi, C. G. Saravanan
Summary: The study found that low viscous biofuels blended with diesel can serve as an efficient substitute fuel, improving brake thermal efficiency, reducing CO2 emissions and other pollutants, but showing higher NO emissions. Among them, wintergreen oil stands out as a biofuel with relatively high density and low viscosity, showing advantages in engine performance.
Editorial Material
Energy & Fuels
Fethi Aloui, Varuvel Edwin Geo
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Engineering, Chemical
Ahmad Al Saabi, Heni Dallagi, Fehti Aloui, Christine Faille, Gaetan Rauwel, Laurent Wauquier, Laurent Bouvier, Thierry Benezech
Summary: This study investigated the efficiency of using flowing foams to remove Bacillus spores from stainless steel surfaces in food industry cleaning operations. Under specific conditions, foams were able to achieve high removal rates at the beginning of the cleaning process, possibly due to local high wall shear stress fluctuations and capillary forces.
JOURNAL OF FOOD ENGINEERING
(2021)
Article
Energy & Fuels
V. Edwin Geo, S. Thiyagarajan, Ankit Sonthalia, T. Prakash, Sary Awad, Fethi Aloui, Arivalagan Pugazhendhi
Summary: This study investigates the reduction of CO2 emissions from a CRDI engine by using low carbon biofuels, hydrogen induction, and a zeolite-based after-treatment system. Results show that these methods can significantly reduce CO2 and smoke emissions, as well as improve engine efficiency.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2021)
Article
Mechanics
Hannes Deponte, Donia Djendar, Tim Eckert, Fethi Aloui, Wolfgang Augustin, Stephan Scholl
Summary: The study focuses on the influence of fluid dynamics on particle transport through experimental determination of three-dimensional velocity fields using stereoscopic micro particle image velocimetry (3D-mu PIV) of a suspension in a flow channel. The research quantifies the impact of process parameters (flow velocity, particle concentration, dimple geometry) on turbulence, heat transfer, and particle deposition and removal. The formation of an oscillating vortex inside the dimple is experimentally proven to explain the high heat transfer and low fouling propensity of dimpled surfaces.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Engineering, Mechanical
Shima Mahmoudirad, Ebrahim Shirani, Fethi Aloui
Summary: This study investigates the vortices and fluid flow structure under different inner cylinder rotation modes by changing parameters. It is found that as the Womersley number increases, there is a time delay in flow following the boundary condition and the critical Taylor number values differ from steady-state conditions.
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING
(2021)
Proceedings Paper
Engineering, Multidisciplinary
Houda Hachem, Ramla Gheith, Fethi Aloui
Summary: This study focuses on the performance of a Stirling engine in unsteady laminar regime and its regenerator properties. It is found that finding the suitable regenerator material can reduce losses and improve the overall performance of the engine.
PROCEEDINGS OF ASME 2021 FLUIDS ENGINEERING DIVISION SUMMER MEETING (FEDSM2021), VOL 1
(2021)
Article
Energy & Fuels
V. Edwin Geo, G. Nagarajan, B. Nagalingam, Fethi Aloui, Mohand Tazerout
Article
Environmental Sciences
Hiba Rejeb, Emna Berrich, Mohamed Hachemi Chahbani, Fethi Aloui
INTERNATIONAL JOURNAL OF GLOBAL WARMING
(2020)
Article
Engineering, Multidisciplinary
M. A. Modaresi, E. Shirani, M. Charmiyan, F. Aloui, A. Koched, M. Pavageau
Proceedings Paper
Engineering, Mechanical
Lamia Gaied, Emna Berrich, Fethi Aloui, Marc Lippert, Laurent Keirsbulck, Maxence Bigerelle
PROCEEDINGE OF THE ASME/JSME/KSME JOINT FLUIDS ENGINEERING CONFERENCE, 2019, VOL 1
(2019)
Proceedings Paper
Engineering, Mechanical
Fethi Aloui, Amal Elawady, Khaled J. Hammad
PROCEEDINGE OF THE ASME/JSME/KSME JOINT FLUIDS ENGINEERING CONFERENCE, 2019, VOL 1
(2019)
Article
Engineering, Mechanical
Fethi Aloui, Lamia Gaied, Wafik Abassi, Marc Lippert, Maxence Bigerelle
MECHANICS & INDUSTRY
(2019)
Article
Thermodynamics
Houda Hachem, Ramla Gheith, Fethi Aloui, Sebastien Delprat, Sebastien Paganelli
INTERNATIONAL JOURNAL OF EXERGY
(2019)
Article
Energy & Fuels
Shitong Fang, Houfan Du, Tao Yan, Keyu Chen, Zhiyuan Li, Xiaoqing Ma, Zhihui Lai, Shengxi Zhou
Summary: This paper proposes a new type of nonlinear VIV energy harvester (ANVEH) that compensates for the decrease in peak energy output at low wind speeds by introducing an auxiliary structure. Theoretical and experimental results show that ANVEH performs better than traditional nonlinear VIV energy harvesters under various system parameter variations.
Article
Energy & Fuels
Wei Jiang, Shuo Zhang, Teng Wang, Yufei Zhang, Aimin Sha, Jingjing Xiao, Dongdong Yuan
Summary: A standardized method was developed to evaluate the availability of solar energy resources in road areas, which combined the Analytic Hierarchy Process (AHP) and the Geographic Information System (GIS). By analyzing critical factors and using a multi-indicator evaluation method, the method accurately evaluated the utilization of solar energy resources and guided the optimal location selection for road photovoltaic (PV) projects. The results provided guidance for the application of road PV projects and site selection for route corridors worldwide, promoting the integration of transportation and energy.
Article
Energy & Fuels
Chang Liu, Jacob A. Wrubel, Elliot Padgett, Guido Bender
Summary: The study investigates the effects of coating defects on the performance of the anode porous transport layer (PTL) in water electrolyzers. The results show that an increasing fraction of uncoated regions on the PTL leads to decreased cell performance, with continuous uncoated regions having a more severe impact compared to multiple thin uncoated strips.
Article
Energy & Fuels
Marcos Tostado-Veliz, Xiaolong Jin, Rohit Bhakar, Francisco Jurado
Summary: In this paper, a coordinated charging price mechanism for clusters of parking lots is proposed. The research shows that enabling vehicle-to-grid characteristics can bring significant economic benefits for users and the cluster coordinator, and vehicle-to-grid impacts noticeably on the risk-averse character of the uncertainty-aware strategies. The developed pricing mechanism can reduce the cost for users, avoiding to directly translate the energy cost to charging points.
Article
Energy & Fuels
Duan Kang
Summary: Building an energy superpower is a key strategy for China and a long-term goal for other countries. This study proposes an evaluation system and index for measuring energy superpower, and finds that China has significantly improved its ranking over the past 21 years, surpassing other countries.
Article
Energy & Fuels
Fucheng Deng, Yifei Wang, Xiaosen Li, Gang Li, Yi Wang, Bin Huang
Summary: This study investigated the synergistic blockage mechanism of sand and hydrate in gravel filling layer and the evolution of permeability in the layer. Experimental models and modified permeability models were established to analyze the effects of sand particles and hydrate formation on permeability. The study provided valuable insights for the safe and efficient exploitation of hydrate reservoirs.
Article
Energy & Fuels
Hao Wang, Xiwen Chen, Natan Vital, Edward Duffy, Abolfazl Razi
Summary: This study proposes a HVAC energy optimization model based on deep reinforcement learning algorithm. It achieves 37% energy savings and ensures thermal comfort for open office buildings. The model has a low complexity, uses a few controllable factors, and has a short training time with good generalizability.
Article
Energy & Fuels
Moyue Cong, Yongzhuo Gao, Weidong Wang, Long He, Xiwang Mao, Yi Long, Wei Dong
Summary: This study introduces a multi-strategy ultra-wideband energy harvesting device that achieves high power output without the need for external power input. By utilizing asymmetry, stagger array, magnetic coupling, and nonlinearity strategies, the device maintains a stable output voltage and high power density output at non-resonant frequencies. Temperature and humidity monitoring are performed using Bluetooth sensors to adaptively assess the device.
Article
Energy & Fuels
Tianshu Dong, Xiudong Duan, Yuanyuan Huang, Danji Huang, Yingdong Luo, Ziyu Liu, Xiaomeng Ai, Jiakun Fang, Chaolong Song
Summary: Electrochemical water splitting is crucial for hydrogen production, and improving the hydrogen separation rate from the electrode is essential for enhancing water electrolyzer performance. However, issues such as air bubble adhesion to the electrode plate hinder the process. Therefore, a methodology to investigate the two-phase flow within the electrolyzer is in high demand. This study proposes using a microfluidic system as a simulator for the electrolyzer and optimizing the two-phase flow by manipulating the micro-structure of the flow.
Article
Energy & Fuels
Shuo Han, Yifan Yuan, Mengjiao He, Ziwen Zhao, Beibei Xu, Diyi Chen, Jakub Jurasz
Summary: Giving full play to the flexibility of hydropower and integrating more variable renewable energy is of great significance for accelerating the transformation of China's power energy system. This study proposes a novel day-ahead scheduling model that considers the flexibility limited by irregular vibration zones (VZs) and the probability of flexibility shortage in a hydropower-variable renewable energy hybrid generation system. The model is applied to a real hydropower station and effectively improves the flexibility supply capacity of hydropower, especially during heavy load demand in flood season.
Article
Energy & Fuels
Zhen Wang, Kangqi Fan, Shizhong Zhao, Shuxin Wu, Xuan Zhang, Kangjia Zhai, Zhiqi Li, Hua He
Summary: This study developed a high-performance rotary energy harvester (AI-REH) inspired by archery, which efficiently accumulates and releases ultralow-frequency vibration energy. By utilizing a magnetic coupling strategy and an accumulator spring, the AI-REH achieves significantly accelerated rotor speeds and enhanced electric outputs.
Article
Energy & Fuels
Yi Yang, Qianyi Xing, Kang Wang, Caihong Li, Jianzhou Wang, Xiaojia Huang
Summary: In this study, a novel hybrid Quantile Regression (QR) model is proposed for Probabilistic Load Forecasting (PLF). The model integrates causal dilated convolution, residual connection, and Bidirectional Long Short-Term Memory (BiLSTM) for multi-scale feature extraction. In addition, a Combined Probabilistic Load Forecasting System (CPLFS) is proposed to overcome the inherent flaws of relying on a single model. Simulation results show that the hybrid QR outperforms traditional models and CPLFS exceeds the best benchmarks in terms of prediction accuracy and stability.
Article
Energy & Fuels
Wen-Jiang Zou, Young-Bae Kim, Seunghun Jung
Summary: This paper proposes a dynamic prediction model for capacity fade in vanadium redox flow batteries (VRFBs). The model accurately predicts changes in electrolyte volume and capacity fade, enhancing the competitiveness of VRFBs in energy storage applications.
Article
Energy & Fuels
Yuechao Ma, Shengtie Wang, Guangchen Liu, Guizhen Tian, Jianwei Zhang, Ruiming Liu
Summary: This paper focuses on the balance of state of charge (SOC) among multiple battery energy storage units (MBESUs) and bus voltage balance in an islanded bipolar DC microgrid. A SOC automatic balancing strategy is proposed considering the energy flow relationship and utilizing the adaptive virtual resistance algorithm. The simulation results demonstrate the effectiveness of the proposed strategy in achieving SOC balancing and decreasing bus voltage unbalance.
Article
Energy & Fuels
Raad Z. Homod, Basil Sh. Munahi, Hayder Ibrahim Mohammed, Musatafa Abbas Abbood Albadr, Aissa Abderrahmane, Jasim M. Mahdi, Mohamed Bechir Ben Hamida, Bilal Naji Alhasnawi, A. S. Albahri, Hussein Togun, Umar F. Alqsair, Zaher Mundher Yaseen
Summary: In this study, the control problem of the multiple-boiler system (MBS) is formulated as a dynamic Markov decision process and a deep clustering reinforcement learning approach is applied to obtain the optimal control policy. The proposed strategy, based on bang-bang action, shows superior response and achieves more than 32% energy saving compared to conventional fixed parameter controllers under dynamic indoor/outdoor actual conditions.