Article
Energy & Fuels
Cengizhan Cengiz, Salih Ozen Unverdi
Summary: In this study, the combustion characteristics and emissions of a heavy-duty direct injection diesel engine under early intake valve closing strategy are evaluated. The results show that the strategy can improve combustion efficiency, reduce fuel consumption and NOx emissions. However, it also leads to increased CO emissions when used with EGR.
Article
Chemistry, Multidisciplinary
Jing Chen, Yan Su, Fangxi Xie
Summary: The potential of a transient control method called model-based engine charge control (MCCT) to reduce nitrogen oxide (NOx) emissions of a light-duty diesel vehicle was investigated. The MCCT function was activated by calibrating factor maps adjusted for various parameters. The relationship between electronic control unit signals and NOx emissions was analyzed during both the worldwide harmonized light-duty test cycle (WLTC) and real driving emission (RDE) cycle. The results showed that MCCT could achieve different degrees of reduction in engine-out and tail-pipe NOx emissions during WLTC and RDE.
Article
Chemistry, Multidisciplinary
Jing Chen, Yan Su, Fangxi Xie
Summary: The potential of using MCCT to reduce NOx emissions in a light-duty diesel vehicle was investigated in this study, focusing on the WLTC and RDE driving cycles. The MCCT function was activated by calibrating factor maps, and the relationship between electronic control unit signals and NOx emissions was analyzed. Results showed that MCCT could achieve varying degrees of reduction in engine-out and tail-pipe NOx emissions in both the WLTC and RDE cycles.
Article
Energy & Fuels
Kangmin Ju, Joonsuk Kim, Jungsoo Park
Summary: This study demonstrates the feasibility of using a diesel engine as a power generator for electric vehicles, and shows that downsized diesel engines have the potential to improve power output performance.
Article
Thermodynamics
Wei Zhang, Chonglin Song, Gang Lv, Fengrong Bi, Yuehan Qiao, Lin Wang, Xuyang Zhang
Summary: This study investigated the properties and oxidation of in-cylinder soot from a diesel engine fueled with n-heptane under simulated exhaust gas recirculation (EGR) conditions. It was found that EGR addition enhances the mass-based specific rate of soot oxidation, but reduces flame temperature and concentrations of O-2 and OH, leading to decreased soot surface oxidation rates. Additionally, the characterization of soot properties showed that EGR decreases structural ordering and results in the formation of more oxygenated and aliphatic C-H groups on the soot surface, favoring soot oxidation during combustion processes.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Energy & Fuels
Mohammed A. Fayad, Slafa I. Ibrahim, Salman H. Omran, Francisco J. Martos, Tawfik Badawy, Ayad M. Al Jubori, Hayder A. Dhahad, Miqdam T. Chaichan
Summary: This study investigated the effects of adding CuO2 nanoparticles and exhaust gas recirculation (EGR) on combustion characteristics and soot nanoparticle morphology in a diesel engine. The results showed that the addition of CuO2 nanoparticles improved combustion characteristics and reduced exhaust emissions. Furthermore, combining CuO2 with EGR technology further reduced NOX emissions.
Article
Engineering, Chemical
Bowen Zhao, Xingyu Liang, Kun Wang, Xu Lv, Yajun Wang
Summary: This study focused on the influence of recirculated soot particles via exhaust gas recirculation (EGR) on the characteristics of exhaust soot particles. The results showed that recirculated soot particles underwent in-cylinder oxidation, resulting in smaller primary particle size, longer fringe length, smaller separation distance and tortuosity, as well as lower relative amount of aliphatic C-H group and oxidation reactivity. The higher graphitization degree of recirculated soot particles led to earlier internal burning during oxidation, resulting in hollow structure at 50% and 75% burn-off stages.
JOURNAL OF AEROSOL SCIENCE
(2023)
Review
Engineering, Environmental
Tao Cai, Dan Zhao, Ephraim Gutmark
Summary: This article provides an overview of the latest research progress in ammonia combustion, summarizing the reaction mechanisms, NOx generation mechanism and mitigation strategies, and the impact of ammonia on soot formation. Furthermore, technical challenges and future research prospects in ammonia combustion with lower NOx emissions are discussed.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Thermodynamics
Wei Zhang, Chenyang Fan, Gang Lyu, Yunqiang Li, Ye Liu, Chenxi Wang, Chonglin Song
Summary: To reduce diesel soot emissions, it is important to understand the properties of soots generated from main-injection combustion and post-injection combustion. This study focused on the primary particle size, nanostructure, and mass of main-soot and post-soot during the combustion process. In-cylinder soot samples were obtained using a total cylinder sampling system, and high-resolution transmission electron microscopy was used to determine particle size and nanostructure. Post-soot was simulated by adding dimethyl ether to the intake gas. The results showed that the primary particle size of post-soot was smaller than that of main-soot, and both soots exhibited similar trends in nanostructure throughout the combustion process.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Pan Wang, Zonglin Li, Chengcheng Ao, Lidong Zhang, Lili Lei
Summary: The thermal gravimetric analysis and in-situ Fourier transform infrared spectrometer were used to evaluate the effects of metal oxide doping on the catalytic combustion performance of Ce-based catalysts. The results showed that K and Ag metal oxides improved the NOx synergistic oxidation performance, while Mn and Zr metal oxides had a negative impact. The doping ratio and hydrothermal aging time also influenced the combustion performance and NO2/NO ratio.
COMBUSTION AND FLAME
(2022)
Article
Thermodynamics
Fabio Berni, Fabio Mortellaro, Valentina Pessina, Stefano Paltrinieri, Francesco Pulvirenti, Vincenzo Rossi, Massimo Borghi, Stefano Fontanesi
Summary: This study aims to provide a robust numerical framework for reliable simulation of gaseous emissions and a dedicated post-processing method for fair comparison between simulations and experiments. The developed approach shows good agreement between simulations and experiments by analyzing different injection timings of a high-performance engine under part-load and low rpm conditions.
INTERNATIONAL JOURNAL OF ENGINE RESEARCH
(2023)
Article
Thermodynamics
Jayashish Kumar Pandey, M. H. Dinesh, G. N. Kumar
Summary: IC engines, the backbone of transportation sector, are facing energy insecurity and strict environmental norms. Hydrogen and its derivatives are seen as promising options for revival. Comparative study on NH3/H2 and hydrogen shows that NH3/H2 exhibits better combustion and reduced NOx emissions, with some trade-offs in terms of cycle-by-cycle variations and ignition range. Moreover, NH3/H2 is more efficient in controlling NOx compared to hydrogen. However, the study has limitations in quantitative analysis and NH3 emissions, which need further investigation.
Article
Thermodynamics
Jayashish Kumar Pandey, G. N. Kumar
Summary: Hydrogen as a green fuel can improve the combustion efficiency and reduce NOx emissions in SI engines by optimizing operating parameters and using NOx mitigation techniques. However, high EGR rates can lead to poor combustion quality and reduced engine reliability.
INTERNATIONAL JOURNAL OF ENGINE RESEARCH
(2023)
Article
Energy & Fuels
M. Gowthama Krishnan, Sundararajan Rajkumar
Summary: The study found that in dual fuel combustion, adjusting the start of injection and implementing exhaust gas recirculation can effectively reduce nitrogen oxide emissions. Compared to conventional combustion mode, significant reductions in NOx emissions were achieved, around 50%, for diesel and biodiesel, recommending the use of a start of injection at 25 degrees before top dead center and 10% EGR.
Article
Energy & Fuels
M. Gowthama Krishnan, Sundararajan Rajkumar
Summary: The study investigated the impact of start of injection (SOI) and exhaust gas recirculation (EGR) on reducing NOx emissions in dual fuel combustion (DFC). It was found that retarding SOIs and implementing 10% EGR led to significant reductions in NOx emissions for diesel, B20, and B100 fuels, compared to conventional combustion mode. Overall, DFC with a SOI of 25 degrees CA before top dead center and 10% EGR was identified as suitable operating conditions for emission reduction.
Article
Engineering, Multidisciplinary
Hamid Taghavifar
Summary: In this study, an active suspension system is developed using an EKF-NN framework to address the inherent drawbacks of the suspension system of IWM-based electric vehicles, and a vibration absorber is employed to further optimize the vehicle design, improving ride comfort and handling performance.
Article
Chemistry, Physical
Hadi Taghavifar, Hamid Taghavifar
Summary: Energy management of hybrid photovoltaic (PV)-battery systems is a challenging task due to their complex and nonlinear characteristics, but a novel adaptive robust control framework has been proposed in this study to optimize the system's performance. This framework ensures global asymptotic stability and improved transient performance compared to benchmark studies.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Automation & Control Systems
Masoud Shirzadeh, Abdollah Amirkhani, Nastaran Tork, Hamid Taghavifar
Summary: This paper presents an adaptive and robust control strategy based on T2FNN for quadrotor trajectory tracking, which outperforms common SMC in controlling both the position and orientation. By optimizing parameters using COA, the proposed approach shows superior trajectory tracking performance compared to GA, PSO, and ACO. The stability and convergence of the COA algorithm in optimizing trajectory tracking control are also demonstrated in this study.
Editorial Material
Engineering, Electrical & Electronic
Guofa Li, Cristina Olaverri-Monreal, Xiaobo Qu, Changxu Sean Wu, Shengbo Eben Li, Hamid Taghavifar, Yang Xing, Shen Li
IEEE INTELLIGENT TRANSPORTATION SYSTEMS MAGAZINE
(2022)
Article
Green & Sustainable Science & Technology
Hadi Taghavifar
Summary: In this study, the potential of gaseous fuels such as hydrogen, methane, and hythane in combination with diesel fuel is assessed. The results show that the entropy generation in hythane and hydrogen is higher compared to diesel, while water injection can reduce entropy. The study also compares the engine performance and emissions characteristics of different fuel blends.
ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY
(2023)
Article
Engineering, Mechanical
Khoshnam Shojaei, Hamid Taghavifar
Summary: In this paper, an observer-based PID controller is proposed to improve the transient and steady-state performance of an autonomous tractor with multiple trailer units. By compensating for the negative effect of path curvature during trailer turning, the controller aims to keep the last trailer on a desired trajectory without deviation. The control strategy involves model derivation, nonlinear transformation, and neural network adaptive PID control, ensuring fast convergence and high accuracy of tracking errors.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE
(2022)
Article
Energy & Fuels
Ali Jabbarzadeh Ghandilou, Hadi Taghavifar
Summary: Numerical studies show that low temperature biodiesel spray injection induces more air entrainment to the spray boundary compared to diesel and high temperature biodiesel spray. The normalized parcel density for biodiesel is 12% larger than diesel and peaks at a shorter distance from the injection point.
Article
Engineering, Mechanical
Hamid Taghavifar, Leyla Taghavifar, Chuan Hu, Chongfeng Wei, Yechen Qin
Summary: In this paper, a novel algorithm combining optimal reinforcement learning and risk assessment is proposed for motion planning and path following of automated cars. The algorithm utilizes a probabilistic function-based collision avoidance strategy and nonlinear model predictive control (NMPC) to approximate optimal steering input and ensure stable travel speed for the ego vehicle. The proposed algorithm is evaluated using different driving scenarios.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING
(2023)
Article
Engineering, Mechanical
Hamid Taghavifar
Summary: This paper introduces a robust adaptive control system for high-speed autonomous vehicles in case the system dynamics are unknown or unavailable. Unlike previous studies, the entire dynamics of the autonomous vehicle are considered unknown. The developed framework shows effectiveness and robustness in navigating the vehicle alongside the desired trajectory, outperforming other reported studies subject to various external disturbances.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING
(2023)
Article
Computer Science, Artificial Intelligence
Hamid Taghavifar, Khoshnam Shojaei
Summary: This paper proposes an improved control algorithm based on a robust adaptive neural network trained with integral sliding mode, which also considers the contribution of active front steering and direct yaw moment control for critical driving scenarios. Additionally, a super-twisting ESO disturbance observer is developed to estimate disturbances imposed on the car during emergency maneuvers. Experimental results show that the proposed controller successfully stabilizes the handling dynamics and enhances the path-tracking performance compared to previous methods.
Article
Green & Sustainable Science & Technology
Hamid Jalilnezhad, Yousef Abbaspour-Gilandeh, Vali Rasooli-Sharabiani, Aref Mardani, Jose Luis Hernandez-Hernandez, Jose Antonio Montero-Valverde, Mario Hernandez-Hernandez
Summary: This research predicts fuel consumption of agricultural tractors using a convolutional neural network. Field experiments were conducted and factors such as soil type, soil conditions, tool parameters, and operation parameters were considered. The results showed high prediction accuracy and low error, indicating that optimizing parameters like working depth, tire inflation pressure, and forward speed can help reduce fuel consumption.
Article
Automation & Control Systems
Ardashir Mohammadzadeh, Hamid Taghavifar, Chunwei Zhang, Khalid A. Alattas, Jinping Liu, Mai The Vu
Summary: This study introduces a robust type-3 fuzzy controller implementation for the path-tracking task of driverless cars during critical driving conditions and subject to exogenous disturbances. The proposed scheme is independent of the parameter information and assumes unknown and non-linear system dynamics. Control inputs are constructed to improve robustness and ensure stability by leveraging the Lyapunov stability theorem and Barbalat's lemma. Also, a predicate scheme based on non-linear predictive control technique is introduced to enhance the lateral displacement.
IET CONTROL THEORY AND APPLICATIONS
(2023)
Article
Engineering, Mechanical
Hamid Taghavifar, Ardashir Mohammadzadeh
Summary: This paper proposes a novel control framework for the path-tracking task of autonomous ground vehicles (AGVs). The control system utilizes a nonlinear adaptive approach, combining integral backstepping with terminal sliding mode control. The controller achieves finite time convergence, robustness, and a chatter-free response by integrating integral action and terminal sliding mode. Additionally, adaptive control compensators are developed to ensure robustness against unknown disturbances. High-fidelity cosimulations are conducted to validate the effectiveness of the proposed control scheme.
Article
Multidisciplinary Sciences
Sajjad Derafshpour, Morteza Valizadeh, Aref Mardani
Summary: The research aimed to improve the accuracy of the Wismer-Luth model in predicting cone index by utilizing three neural networks, with the generalized regression neural network showing the best performance. It was also found that using forward velocity or multi-pass factors had minimal impact on model improvement, but incorporating all parameters (velocity, load, and number of passes) significantly increased model accuracy.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2021)
Article
Thermodynamics
Pengcheng Zhao, Jingang Wang, Liming Sun, Yun Li, Haiting Xia, Wei He
Summary: The production of green hydrogen through water electrolysis is crucial for renewable energy utilization and decarbonization. This research explores the optimal electrode configuration and system design of compactly-assembled industrial electrolyzer. The findings provide valuable insights for industrial application of water electrolysis equipment.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
V. Baiju, P. Abhishek, S. Harikrishnan
Summary: Thermally driven adsorption desalination systems (ADS) have gained attention as an eco-friendly solution for water scarcity. However, they face challenges related to low water productivity and scalability. To overcome these challenges, integrating ADS with other desalination technologies can create a small-scale hybrid system. This study proposes integrating ADS with a Thermo Electric Dehumidification (TED) unit to enhance its performance.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
C. X. He, Y. H. Liu, X. Y. Huang, S. B. Wan, Q. Chen, J. Sun, T. S. Zhao
Summary: A decentralized centroid multi-path RC network model is constructed to improve the temperature prediction accuracy compared to traditional RC models. By incorporating multiple heat flow paths and decentralizing thermal capacity, a more accurate prediction is achieved.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Chaoying Li, Meng Wang, Nana Li, Di Gu, Chao Yan, Dandan Yuan, Hong Jiang, Baohui Wang, Xirui Wang
Summary: There is an urgent need to shift away from heavy dependence on fossil fuels and embrace renewable energy sources, particularly in the energy-intensive oil refining process. This study presents an innovative concept called the Solar Oil Refinery, which applies solar energy in oil refining. A solar multi-energies-driven hybrid chemical oil refining system that utilizes solar pyrolysis and electrolysis has been developed, significantly improving solar utilization efficiency, cracking rate, and hydrogen yield.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Chao Ma, Guanghui Wang, Dingbiao Wang, Xu Peng, Yushen Yang, Xinxin Liu, Chongrui Yang, Jiaheng Chen
Summary: This study proposes a bio-inspired fish-tail wind rotor to improve the wind power efficiency of the traditional Savonius rotor. Through transient simulations and orthogonal experiments, the key factors affecting the performance are identified. A response surface model is constructed to optimize the power coefficient, resulting in an improvement of 9.4% and 6.6% compared to the Savonius rotor.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Sina Bahmanziari, Abbas-Ali Zamani
Summary: This paper proposes a new framework for improving electrical energy harvesting from piezoelectric smart tiles through a combination of magnetic plucking, mechanical impact, and mechanical vibration force mechanisms. Experimental results demonstrate a significant increase in energy yield and average energy harvesting time compared to other mechanisms.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Nanjiang Dong, Tao Zhang, Rui Wang
Summary: This study establishes a multiobjective mixed-variable configuration optimization model for a comprehensive combined cooling, heating, and power energy system, and proposes an efficient generating operator to optimize this model. The experimental results show that the proposed algorithm performs better than other state-of-the-art algorithms.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Ahmed E. Mansy, Eman A. El Desouky, Tarek H. Taha, M. A. Abu-Saied, Hamada El-Gendi, Ranya A. Amer, Zhen-Yu Tian
Summary: This study aims to convert office paper waste into bioethanol through a sustainable pathway. The results show that physiochemical and enzymatic hydrolysis of the waste can yield a high glucose concentration. The optimal conditions were determined using the Box-Behnken design, and a blended membrane was used for ethanol purification.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Sven Klute, Marcus Budt, Mathias van Beek, Christian Doetsch
Summary: Heat pumps are crucial for decarbonizing heat supply, and steam generating heat pumps have the potential to decarbonize the industrial sector. This paper presents the current state, technical and economic data, and modeling principles of steam generating heat pumps.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Le Zhang, To-Hung Tsui, Yen Wah Tong, Pruk Aggarangsi, Ronghou Liu
Summary: This study investigates the effectiveness of a current-carrying-coil-based magnetic field in promoting anaerobic digestion of chicken manure. The results show that the applied magnetic field increases methane yield, decreases carbon dioxide production, and reduces the concentration of ammonia nitrogen. Microbial community analysis reveals the enrichment of certain methanogenic genera and enhanced metabolic pathways. Pilot-scale experiments confirm the technical effectiveness of the magnetic field assistance in enhancing anaerobic digestion of chicken manure.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Bo Chen, Ruiqing Ma, Yang Zhou, Rui Ma, Wentao Jiang, Fan Yang
Summary: This paper presents an advanced energy management strategy for fuel cell hybrid electric heavy-duty vehicles, focusing on speed planning and energy allocation. By utilizing predictive co-optimization control, this strategy ensures safe inter-vehicle distance and minimizes energy demand. Simulation results demonstrate the effectiveness of the proposed method in reducing fuel cell degradation cost and overall operation cost.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Fabio Fatigati, Roberto Cipollone
Summary: Organic Rankine Cycle-based microcogeneration systems that use solar sources to generate electricity and hot water can help reduce CO2 emissions in residential energy-intensive sectors. The adoption of a recuperative heat exchanger in these systems improves efficiency, reduces thermal power requirements, and saves on electricity costs.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Lipeng He, Renwen Liu, Xuejin Liu, Xiaotian Zheng, Limin Zhang, Jieqiong Lin
Summary: This research proposes a piezoelectric-electromagnetic hybrid energy harvester (PEHEH) for low-frequency wave motion and self-sensing wave environment monitoring. The PEHEH shows promising power output and the ability to self-power and self-sense the wave environment.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Shangling Chu, Yang Liu, Zipeng Xu, Heng Zhang, Haiping Chen, Dan Gao
Summary: This paper studies a distributed energy system integrated with solar and natural gas, analyzes the impact of different parameters on its energy utilization and emissions reduction, and obtains the optimal solution through an optimization algorithm. The results show that compared to traditional separation production systems, this integrated system achieves higher energy utilization and greater reduction in carbon emissions.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Thermodynamics
Qingpu Li, Yaqi Ding, Guangming Chen, Yongmei Xuan, Neng Gao, Nian Li, Xinyue Hao
Summary: This paper proposes and studies a piston-type thermally-driven pump with a structure similar to a linear compressor, aiming to eliminate the high-quality energy consumption of existing pumps and replace mechanical pumps. The coupling mechanism of working fluid flow and element dimension is analyzed based on force analysis, and experimental data analysis is used to determine the pump operation stroke. Theoretical simulation is conducted to analyze the correlation mechanism of the piston assembly. The research shows that the thermally-driven pump can greatly reduce power consumption and has potential for industrial applications.
ENERGY CONVERSION AND MANAGEMENT
(2024)