Article
Thermodynamics
Changming Gong, Jingzhen Sun, Fenghua Liu
Summary: The study showed that optimal injection timing of 110 degrees crank angle before top dead center and ignition timing of 21 degrees crank angle before top dead center can achieve the best compromise for a medium compression ratio direct-injection twin-spark plug synchronous ignition methanol engine under steady-state lean-burn conditions. Twin-spark plug synchronous ignition can ensure stable combustion and yield good performance with a medium compression ratio under lean burn conditions.
Article
Thermodynamics
Baodong Ma, Anren Yao, Chunde Yao, Chao Chen, Guofan Qu, Wenchao Wang, Youkai Ai
Summary: This study identified four typical combustion modes in a diesel methanol dual fuel engine, with the first and second modes showing higher thermal efficiency. Diesel plays an important role in igniting methanol and improving combustion under different conditions.
Article
Energy & Fuels
Xinlei Liu, Hammam Aljabri, Niraj Panthi, Abdullah S. AlRamadan, Emre Cenker, Abdullah T. Alshammari, Gaetano Magnotti, Hong G. Im
Summary: This study aimed to identify the best strategy for hydrogen internal combustion engines. Computational simulations were conducted to evaluate the combustion and emission characteristics of four combustion strategies. The DF-DI and SI operations tended to yield higher thermal efficiency, while the DF-DI operation generated the highest nitric oxide emission. The PCC and SI modes were able to fulfill the EU VI regulation limit of NOx emission with relatively high thermal efficiency.
Article
Thermodynamics
Qimeng Duan, Tao Li, Dong Liu, Xiaojun Yin, Ke Zeng, Long Wang
Summary: The study demonstrates that using multiple-injection strategies can improve the combustion efficiency and stability of methanol engines, while reducing cycle-to-cycle variations. In experimental evaluations, the triple-injection strategy shows superior performance, especially in terms of thermal efficiency and nitrogen oxide emissions.
APPLIED THERMAL ENGINEERING
(2024)
Article
Energy & Fuels
Changzhao Jiang, Chongming Wang, Hongming Xu, Haoye Liu, Xiao Ma
Summary: The study found that employing the stratified lean-burn mode in spark-ignition engines can significantly improve fuel economy, with up to a 16% increase if the second injection timing is optimized. The second injection timing also has significant impacts on IMEP, combustion duration, COV, gaseous emission, and particulate number emissions.
Article
Thermodynamics
Junheng Liu, Haoran Ma, Wenwen Liang, Jun Yang, Ping Sun, Xidong Wang, Yongxu Wang, Pan Wang
Summary: The research found that as the MSR increases, the ignition delay of the dual-fuel engine increases, as does the COV, with different combustion characteristics under different loads.
Article
Chemistry, Physical
Gu Xin, Changwei Ji, Shuofeng Wang, Hao Meng, Ke Chang, Jinxin Yang
Summary: This experimental study investigates the suppression of heat release rate in a hydrogen-fueled engine through the addition of ammonia. The results show that adding small amounts of ammonia decreases the combustion rate, prolongs flame development and propagation durations, reduces pressure and heat release rate peaks, and increases peak effective pressure and thermal efficiency. However, it also leads to increased nitrogen oxide emissions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Xiang Li, Yiqiang Pei, Dayou Li, Tahmina Ajmal, Khaqan-Jim Rana, Abdel Aitouche, Raouf Mobasheri, Zhijun Peng
Summary: Global warming is closely related to CO2 emissions, and OFC technology is promising to help reduce CO2 emissions. This study investigates the effects of WI strategies on OFC characteristics in dual-injection SI engines, showing that appropriate WI strategies are beneficial to OFC combustion, but the benefit in fuel economy is limited.
Article
Energy & Fuels
Hao Yuan, Karl Giles, Sipeng Zhu, Simeon Howson, Andrew Lewis, Sam Akehurst, Niall Turner, James Harris, Gavin Fowler, John Geddes
Summary: This study models the impact of direct water injection on the combustion process in a spark ignition engine, highlighting the thermodynamic and chemical-kinetic interactions between gasoline combustion and water injection. It shows that water injection can advance the combustion phasing by reducing in-cylinder temperature, thereby affecting the knock limited spark advance and improving engine performance.
Article
Thermodynamics
Deborah Domingos da Rocha, Fabio de Castro Radicchi, Gustavo Santos Lopes, Marcello Francisco Brunocilla, Paulo Cesar de Ferreira Gomes, Nathalia Duarte Souza Alvarenga Santos, Augusto Cesar Teixeira Malaquias, Fernando Antonio Rodrigues Filho, Jose Guilherme Coelho Baeta
Summary: This study experimentally validated the impact of different water injection strategies on engine combustion parameters, finding that variations in water injection temperature had limited influence on fuel conversion efficiency, while proper injection timing and pressure calibration significantly reduced specific fuel consumption.
Article
Energy & Fuels
Hao Feng, Kaichang Lai, Zunqing Zheng, Sicong Lin, Xiang Wu, Qinglong Tang
Summary: The high octane number and high latent heat of vaporization of methanol are beneficial for suppressing knock and increasing compression ratio in spark ignition engines, leading to improved thermal efficiency. This study investigated the potential of high compression ratio and methanol direct injection (MDI) on the performance of a 1.5-liter spark ignition passenger car engine. The results showed that integrating a high compression ratio of 15.3 and MDI improved brake thermal efficiency (BTE) compared to low CR with gasoline, but also resulted in extended combustion durations and increased THC and CO emissions.
Article
Thermodynamics
Hyunwook Park, Junsun Lee, Narankhuu Jamsran, Seungmook Oh, Changup Kim, Yonggyu Lee, Kernyong Kang
Summary: Synthesis gas (syngas) serves as an intermediary fuel source between traditional carbon-based fuels and hydrogen-based fuels. The comparison between stoichiometric and lean combustion modes in a single-cylinder SI engine reveals the optimal combustion mode for a syngas engine generator. The study highlights the importance of optimizing factors such as compression ratio and intake boosting for improved engine performance. However, differences in power output and thermal efficiency exist between the two combustion modes, emphasizing trade-offs in engine design.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Chemistry, Physical
Xiumin Yu, Zhipeng Hu, Zezhou Guo, Decheng Li, Tianqi Wang, Yinan Li, Jufang Zhang, Tianyang Gong, Yanwei Li
Summary: Ethanol, a carbon-neutral fuel, is widely used in engines. Combining hydrous ethanol with hydrogen can reduce costs and improve combustion performance, especially under lean-burn conditions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
T. Sathish Kumar, B. Ashok
Summary: A novel approach has been explored to examine the most appropriate conditions for methanol flex-fuel operation in a direct injection spark ignition (DISI) engine. The research findings show significant improvement in brake thermal efficiency (BTE) from 18.27% to 27.73%. However, brake-specific fuel consumption (BSFC) increases, with M40 exhibiting the highest value of 506 g/kWhr. On the other hand, carbon monoxide (CO) and hydrocarbon (HC) emissions decrease, while carbon dioxide (CO2) and nitrogen oxides (NOx) emissions increase for blended fuel.
Article
Energy & Fuels
Changming Gong, Zilei Zhang, Jingzhen Sun, Fenghua Liu
Summary: Achieving ideal stratified-charge combustion is the key to obtaining the best performance of a spark-ignition methanol engine under high compression-ratio and ultra-lean burn. The timings of injection and spark have significant effects on mixture formation, combustion, and emissions, with optimal timings resulting in improved engine performance.
Article
Energy & Fuels
Yingna Du, Chen Huang, Wei Jiang, Qiangwei Yan, Yongfei Li, Gang Chen
Summary: In this study, anionic surfactants modified hydrotalcite was used as a flow improver for crude oil under low-temperature conditions. The modified hydrotalcite showed a significant viscosity reduction effect on crude oil. The mechanism of the modified hydrotalcite on viscosity and pour point of crude oil was explored through characterization and analysis of the modified hydrotalcite and oil samples.
Article
Energy & Fuels
Mohammad Saeid Rostami, Mohammad Mehdi Khodaei
Summary: In this study, a hybrid structure, MIL-53(Al)@MWCNT, was synthesized by combining MIL-53(Al) particles and -COOH functionalized multi-walled carbon nanotube (MWCNT). The hybrid structure was then embedded in a polyethersulfone (PES) polymer matrix to prepare a mixed matrix membrane (MMM) for CO2/CH4 and CO2/N2 separation. The addition of MWCNTs prevented MIL-53(Al) aggregation, improved membrane mechanical properties, and enhanced gas separation efficiency.
Article
Energy & Fuels
Yunlong Li, Desheng Huang, Xiaomeng Dong, Daoyong Yang
Summary: This study develops theoretical and experimental techniques to determine the phase behavior and physical properties of DME/flue gas/water/heavy oil systems. Eight constant composition expansion (CCE) tests are conducted to obtain new experimental data. A thermodynamic model is used to accurately predict saturation pressure and swelling factors, as well as the phase boundaries of N2/heavy oil systems and DME/CO2/heavy oil systems, with high accuracy.
Article
Energy & Fuels
Morteza Afkhamipour, Ebad Seifi, Arash Esmaeili, Mohammad Shamsi, Tohid N. Borhani
Summary: Non-conventional amines are being researched worldwide to overcome the limitations of traditional amines like MEA and MDEA. Adequate process and thermodynamic models are crucial for understanding the applicability and performance of these amines in CO2 absorption, but studies on process modeling for these amines are limited. This study used rate-based modeling and Deshmukh-Mather method to model CO2 absorption by DETA solution in a packed column, validated the model with experimental data, and conducted a sensitivity analysis of mass transfer correlations. The study also compared the CO2 absorption efficiency of DETA solution with an ionic solvent [bmim]-[PF6] and highlighted the importance of finding optimum operational parameters for maximum absorption efficiency.
Article
Energy & Fuels
Arastoo Abdi, Mohamad Awarke, M. Reza Malayeri, Masoud Riazi
Summary: The utilization of smart water in EOR operations has gained attention, but more research is needed to understand the complex mechanisms involved. This study investigated the interfacial tension between smart water and crude oil, considering factors such as salt, pH, asphaltene type, and aged smart water. The results revealed that the hydration of ions in smart water plays a key role in its efficacy, with acidic and basic asphaltene acting as intrinsic surfactants. The pH also influenced the interfacial tension, and the aged smart water's interaction with crude oil depended on asphaltene type, salt, and salinity.
Article
Energy & Fuels
Dongao Zhu, Kun Zhu, Lixian Xu, Haiyan Huang, Jing He, Wenshuai Zhu, Huaming Li, Wei Jiang
Summary: In this study, cobalt-based metal-organic frameworks (Co-based MOFs) were used as supports and co-catalysts to confine the NHPI catalyst, solving the leaching issue. The NHPI@Co-MOF with carboxyl groups exhibited stronger acidity and facilitated the generation of active oxygen radicals O2•, resulting in enhanced catalytic activity. This research provides valuable insights into the selection of suitable organic linkers and broadens the research horizon of MOF hybrids in efficient oxidative desulfurization (ODS) applications.
Article
Energy & Fuels
Edwin G. Hoyos, Gloria Amo-Duodu, U. Gulsum Kiral, Laura Vargas-Estrada, Raquel Lebrero, Rail Munoz
Summary: This study investigated the impact of carbon-coated zero-valent nanoparticle concentration on photosynthetic biogas upgrading. The addition of nanoparticles significantly increased microalgae productivity and enhanced nitrogen and phosphorus assimilation. The presence of nanoparticles also improved the quality of biomethane produced.
Article
Energy & Fuels
Yao Xiao, Asma Leghari, Linfeng Liu, Fangchao Yu, Ming Gao, Lu Ding, Yu Yang, Xueli Chen, Xiaoyu Yan, Fuchen Wang
Summary: Iron is added as a flocculant in wastewater treatment and the hydrothermal carbonization (HTC) of sludge produces wastewater containing Fe. This study investigates the effect of aqueous phase (AP) recycling on hydrochar properties, iron evolution and environmental assessment during HTC of sludge. The results show that AP recycling process improves the dewatering performance of hydrochar and facilitates the recovery of Fe from the liquid phase.
Article
Energy & Fuels
He Liang, Tao Wang, Zhenmin Luo, Jianliang Yu, Weizhai Yi, Fangming Cheng, Jingyu Zhao, Xingqing Yan, Jun Deng, Jihao Shi
Summary: This study investigated the influence of inhibitors (carbon dioxide, nitrogen, and heptafluoropropane) on the lower flammability limit of hydrogen and determined the critical inhibitory concentration needed for complete suppression. The impact of inhibitors on explosive characteristics was evaluated, and the inhibitory mechanism was analyzed with chemical kinetics. The results showed that with the increase of inhibitor quantity, the lower flammability limit of hydrogen also increased. The research findings can contribute to the safe utilization of hydrogen energy.
Article
Energy & Fuels
Zonghui Liu, Zhongze Zhang, Yali Zhou, Ziling Wang, Mingyang Du, Zhe Wen, Bing Yan, Qingxiang Ma, Na Liu, Bing Xue
Summary: In this study, high-performance solid catalysts based on phosphotungstic acid (HPW) supported on Zr-SBA-15 were synthesized and evaluated for the one-pot conversion of furfural (FUR) to γ-valerolactone (GVL). The catalysts were characterized using various techniques, and the ratio of HPW and Zr was found to significantly affect the selectivity of GVL. The HPW/Zr-SBA-15 (2-4-15) catalyst exhibited the highest GVL yield (83%) under optimized reaction conditions, and it was determined that a balance between Bronsted acid sites (BAS) and Lewis acid sites (LAS) was crucial for achieving higher catalytic performance. The reaction parameters and catalyst stability were also investigated.
Article
Energy & Fuels
Michael Stoehr, Stephan Ruoff, Bastian Rauch, Wolfgang Meier, Patrick Le Clercq
Summary: As part of the global energy transition, an experimental study was conducted to understand the effects of different fuel properties on droplet vaporization for various conventional and alternative fuels. The study utilized a flow channel to measure the evolution of droplet diameters over time and distance. The results revealed the temperature-dependent effects of physical properties, such as boiling point, liquid density, and enthalpy of vaporization, and showed the complex interactions of preferential vaporization and temperature-dependent influences of physical properties for multi-component fuels.
Article
Energy & Fuels
Yuan Zhuang, Ruikang Wu, Xinyan Wang, Rui Zhai, Changyong Gao
Summary: Through experimental validation and optimization of the chemical kinetic model, it was found that methanol can accelerate the oxidation reaction of ammonia, and methanol can be rapidly oxidized at high concentration. HO2 was found to generate a significant amount of OH radicals, facilitating the oxidation of methanol and ammonia. Rating: 7.5/10.
Article
Energy & Fuels
Radwan M. EL-Zohairy, Ahmed S. Attia, A. S. Huzayyin, Ahmed I. EL-Seesy
Summary: This paper presents a lab-scale experimental study on the impact of diethyl ether (DEE) as an additive to waste cooking oil biodiesel with Jet A-1 on combustion and emission features of a swirl-stabilized premixed flame. The addition of DEE to biodiesel significantly affects the flame temperature distribution and emissions. The W20D20 blend of DEE, biodiesel, and Jet A-1 shows similar flame temperature distribution to Jet A-1 and significantly reduces UHC, CO, and NOx emissions compared to Jet A-1.
Article
Energy & Fuels
Jiang Bian, Ziyuan Zhao, Yang Liu, Ran Cheng, Xuerui Zang, Xuewen Cao
Summary: This study presents a novel method for ammonia separation using supersonic flow and develops a mathematical model to investigate the condensation phenomenon. The results demonstrate that the L-P nucleation model accurately characterizes the nucleation process of ammonia at low temperatures. Numerical simulations also show that increasing pressure and concentration can enhance ammonia condensation efficiency.
Article
Energy & Fuels
Shiyuan Pan, Xiaodan Shi, Beibei Dong, Jan Skvaril, Haoran Zhang, Yongtu Liang, Hailong Li
Summary: Integrating CO2 capture with biomass-fired combined heat and power (bio-CHP) plants is a promising method for achieving negative emissions. This study develops a reliable data-driven model based on the Transformer architecture to predict the flowrate and CO2 concentration of flue gas in real time. The model validation shows high prediction accuracy, and the potential impact of meteorological parameters on model accuracy is assessed. The results demonstrate that the Transformer model outperforms other models and using near-infrared spectral data as input features improves the prediction accuracy.