Article
Energy & Fuels
Huiquan Duan, Ming Jia, Hui Wang, Yaopeng Li, Guangqing Xia
Summary: This study investigates the control mechanism of fuel properties and intake temperature on the low-temperature PODEn/gasoline combustion. Two combustion modes, PPC and R-RCCI, were studied with different fuel regulating methods. The results show that increasing local fuel concentration is more effective in improving combustion efficiency and thermal efficiency in PPC, while the lower local temperature caused by the heat of vaporization of directly injected gasoline significantly influences the combustion process in R-RCCI. R-RCCI can effectively reduce combustion instability, combustion rate, and NOx emissions compared to PPC.
Article
Chemistry, Physical
Reza Mahmoodi, Mortaza Yari, Jafar Ghafouri, Kamran Poorghasemi
Summary: Biogas can be used as a cheaper, renewable fuel in internal combustion engines. However, the variability in raw materials and production process can affect the combustion control. Research has shown that fixing the biogas components can impact the combustion behavior and emissions in internal combustion engines.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Energy & Fuels
Jiaying Pan, Zhen Hu, Zhenhua Pan, Gequn Shu, Haiqiao Wei, Tao Li, Changwen Liu
Summary: Ethanol as an oxygenate additive in gasoline can inhibit knocking tendency, delay auto-ignition timing, and reduce pressure oscillations in combustion. Turbulent mixing and energy density play roles in alleviating knocking intensity and promoting detonation development, but fuel reactivity remains the key factor in strong knocking formation and detonation development.
Article
Engineering, Aerospace
Mujdat Firat, Sehmus Altun, Mutlu Okcu, Yasin Varol
Summary: The combustion characteristics of reactivity controlled compression ignition (RCCI) were investigated using iso-propanol, petroleum diesel, biodiesel, and their blends as fuels. The results showed that increasing the premixed ratio of low-reactivity fuel (iso-propanol) prolonged the ignition delay period, reduced the combustion duration and rate of pressure rise, leading to reduced NO emissions and smoke opacity. Iso-propanol and biodiesel blends demonstrated the best performance in RCCI mode.
PROPULSION AND POWER RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Wenfeng Zhan, Hong Chen, Jiakun Du, Bin Wang, Fangxi Xie, Yuhuai Li
Summary: By modifying the combustion chamber and pre-chamber, stable ultra-lean combustion at a high compression ratio was achieved on the AVL 5400 engine, resulting in a breakthrough of 51.10% gross indicated thermal efficiency. Pre-chamber turbulent jet ignition can significantly expand the lean burn limit of spark ignition while reducing fuel consumption and nitrogen oxide emissions.
Article
Energy & Fuels
Mujdat Firat, Mutlu Okcu, Sehmus Altun, Yasin Varol
Summary: In this study, a detailed 3D combustion model was developed in ANSYS-Forte environment for the application of natural gas to RCCI engines, and validated with experimental data. The results showed that the combustion and emission characteristics changed with the increase of premixed ratio, but the engine efficiency started to decrease.
Article
Energy & Fuels
Akhilendra Pratap Singh, Vikram Kumar, Avinash Kumar Agarwal
Summary: Stricter emission norms, scarce availability of conventional fuel resources, and moderate engine efficiency are major concerns for both spark ignition (SI) and compression ignition (CI) engines. The use of advanced low-temperature combustion technologies, particularly reactivity-controlled compression ignition (RCCI) mode combustion, can address these issues effectively. RCCI mode combustion offers lower exhaust emissions and higher brake thermal efficiency compared to CI mode combustion, making it a promising solution for improved engine performance and reduced emissions.
Article
Energy & Fuels
Huiquan Duan, Ming Jia, Yaopeng Li, Tianyou Wang
Summary: The study investigated RCCI with reverse reactivity stratification (RRCCI) with gasoline and PODEn as fuels at low and medium loads in a light-duty compression-ignition engine. Results showed that R-RCCI has moderate combustion rate and efficiency, with the highest indicated thermal efficiency (ITE) and significantly lower NOx and soot emissions compared to PPC. R-RCCI also strikes a better balance between premixed combustion and combustion temperature, leading to very low soot emissions at low and medium loads.
Article
Engineering, Multidisciplinary
Mior A. Said, Ibrahim B. Dalha, Zainal A. Abdul Karim, Mohammed El-Adawy
Summary: Reactivity-controlled compression ignition (RCCI) combustion is a combustion technique that enhances combustion efficiency by blending fuels with different reaction rates. However, at low loads, techniques used to control nitrogen oxides (NOx) and soot emissions increase carbon monoxide (CO) and unburned hydrocarbon (UHC) emissions. Modified injection and proper biogas mixing can further reduce these emissions and achieve a trade-off with other emissions.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Johan C. G. Andrae, Tamas Kovacs
Summary: In this study, a validated chemical kinetic model was used to simulate the combustion conditions of multicomponent gasoline surrogate fuels in order to evaluate their potential for use in Reactivity Controlled Compression Ignition (RCCI) combustion. The results show that 1,3-cyclohexadiene (CYC6H8) and its isomer lC6H8 have the potential to be used as the high reactivity directly injected fuel in dual-fuel RCCI combustion, especially at high load conditions.
Article
Energy & Fuels
Sohayb Bahrami, Kamran Poorghasemi, Hamit Solmaz, Alper Calam, Duygu Ipci
Summary: The RCCI mode, using both low reactivity and high reactivity fuels for mixture formation, has shown potential in reducing harmful emissions and fuel consumption. The addition of hydrogen in RCCI combustion has been found to increase maximum in-cylinder pressure and decrease soot emissions.
Article
Energy & Fuels
Lker Ors, Savas Yelbey, Halil Erdi Gulcan, Bahar Sayin Kul, Murat Ciniviz
Summary: This study analyzes the combustion behavior of an SI engine and evaluates its thermodynamic performance through energy and exergy analysis. The addition of small amounts of ethanol and methanol to gasoline is compared with gasoline as the reference fuel. The study demonstrates that the addition of ethanol and methanol increases the maximum in-cylinder pressure, while reducing the average in-cylinder gas temperature and increasing the pressure increase rates. The volumetric addition of ethanol/methanol to gasoline has a decreasing effect on thermal and exergetic efficiency values.
Article
Chemistry, Multidisciplinary
Michal Puskar, Jozef Zivcak, Melichar Kopas, Pavol Tarbajovsky, Matus Lavcak
Summary: The presented scientific study focuses on a comprehensive analysis of power output and emission parameters of an experimental motorcycle. While there is existing theoretical and experimental data for L-category vehicles, there is generally a lack of information on the experimental tests and power output characteristics of high-power racing engines. This is due to motorcycle producers' reluctance to disclose their latest information, especially regarding advanced high-tech applications. The study focuses on the main results obtained from operational tests conducted on the motorcycle engine in two testing cases.
Article
Energy & Fuels
Melih Yildiz, Bilge Albayrak Ceper
Summary: Low temperature combustion concepts have emerged as a solution to reduce emissions in internal combustion engines. Among these concepts, reactivity controlled compression ignition (RCCI) has the potential for a wider operating range. This study compared high-exhaust gas recirculation (EGR) compression ignition (CI) and gasoline/diesel fueled RCCI combustion modes in terms of combustion, performance, and emissions. The results showed that RCCI combustion achieved lower nitrogen oxide (NO) emissions and improved smoke emissions compared to high-EGR CI combustion. Furthermore, RCCI combustion exhibited slightly higher brake thermal efficiencies (BTE).
Article
Green & Sustainable Science & Technology
Xiongbo Duan, Lubin Xu, Linxun Xu, Pengfei Jiang, Tian Gan, Haibo Liu, Shaobo Ye, Zhiqiang Sun
Summary: The global push for carbon neutrality has driven research into low-carbon or zero-carbon fuels for the transportation sector. This study investigates the use of industrial by-product hydrogen (IPH) in spark ignition (SI) engines and compares its performance with gasoline. The experimental results show that the SI engine fueled with IPH has improved fuel efficiency and lower emissions of CO and HC compared to the gasoline engine. However, it has higher NOx emissions. Overall, the SI engine fueled with IPH outperforms the gasoline engine in terms of fuel economy.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Energy & Fuels
Jeonghyun Park, Jeong Hwan Park, Suhan Park
Article
Thermodynamics
Mengzhao Chang, Hyung Ik Kim, Jeong Hwan Park, Jin Wang, Suhan Park
Summary: This study visualized the ball (needle) motion and near-field spray characteristics of a gasoline direct injection injector under different injection conditions, and analyzed the effect of the injector's internal structure on these characteristics. It was found that the ball tilts during stable motion and holes with smaller inlet angles display better atomization characteristics.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Energy & Fuels
Mengzhao Chang, Jeonghyun Park, Byunggyun Kim, Jeong Hwan Park, Sungwook Park, Suhan Park
Summary: This study analyzed the impact of sac-volume in high-pressure GDI injector on ball behavior, initial spray characteristics, and post-injection. Results revealed that a smaller sac volume led to the ball being further away from the center of the nozzle, increased spray tip penetration, and decreased residual fuel discharge at the end of injection.
Article
Engineering, Mechanical
Byunggyun Kim, Seungcheon Ro, Suhan Park, Young-Bae Kim, Byungchul Choi, Seunghun Jung, Dong-Weon Lee
Summary: This study found that the development of cavitation is influenced by the needle position, with cavitation being relatively symmetric when the needle is at the center and asymmetric when there is a bias. The needle position also affects the timing and growth of cavitation.
INTERNATIONAL JOURNAL OF AUTOMOTIVE TECHNOLOGY
(2021)
Article
Energy & Fuels
Seongin Jo, Suhan Park, Chang Sik Lee
Summary: This paper proposes a method for detecting and calculating combustion phases of internal combustion engines based on the difference between combustion and motoring pressures. The results obtained using this method were almost identical to those calculated based on cumulative heat release, with very small errors.
JOURNAL OF ENERGY ENGINEERING
(2021)
Article
Engineering, Mechanical
In Gang Park, Young Chan Lim, Hyn Kyu Suh, Suhan Park
Summary: The study found that an increase in the empirical nozzle discharge coefficient decreases the sac volume pressure and blob injection velocity, while increasing the effective flow exit area; an increase in the time constant of the Kelvin-Helmholtz breakup model delays the primary breakup timing, decreases the number of parcels, and increases average mass, velocity, and droplet diameter.
TRANSACTIONS OF THE KOREAN SOCIETY OF MECHANICAL ENGINEERS B
(2021)
Article
Thermodynamics
Mengzhao Chang, Young Soo Yu, Sungwook Park, Suhan Park
Summary: In this study, the spray atomization characteristics of two GDI injectors with different hole arrangements were measured under subcooled and flash-boiling conditions. The results showed that under flash-boiling conditions, the spray droplet diameter significantly decreased and the spatial distribution of SMD became more uniform.
APPLIED THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
Hyung Jun Kim, Seongin Jo, Sangil Kwon, Jong-Tae Lee, Suhan Park
Summary: This study analyzed the distribution of NOX emissions in vehicles meeting Korea's Euro-6 emission standards under cold and hot start conditions, as well as the relationship between ECU/DCU signals and exhaust emissions. It was found that over 76% of the vehicle models used the LNT + SCR after-treatment system, with ECU and DCU signals controlling emissions-related parameters.
Article
Thermodynamics
Mengzhao Chang, Jeonghyun Park, Hyung Ik Kim, Suhan Park
Summary: The study compares and analyzes the evaporation characteristics of five-hole gasoline direct injection injectors with different hole arrangements under flash-boiling conditions. By calculating the area of the pure evaporation zone, the study reveals the differences and similarities in spray evaporation characteristics of standard-and skew-type injectors under different directions and superheat conditions.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Review
Thermodynamics
Quangkhai Pham, Sungwook Park, Avinash Kumar Agarwal, Suhan Park
Summary: The performance, combustion, and emission characteristics of alternative fuels in dual-fuel mode in compression ignition engines have been thoroughly analyzed. Generally, alternative fuels improve brake specific energy consumption compared to baseline diesel mode but have lower brake thermal efficiency and volumetric efficiency.
Article
Thermodynamics
Seongin Jo, Junepyo Cha, Suhan Park
Summary: This study discusses the exhaust emission characteristics of stoichiometric combustion on DPF and TWC, finding that using simulated-EGR results in high NOx conversion efficiency and significant reduction of soot particles.
Article
Thermodynamics
Quangkhai Pham, Mengzhao Chang, Ankur Kalwar, Avinash Kumar Agarwal, Sungwook Park, Byungchul Choi, Suhan Park
Summary: The macroscopic spray characteristics and internal structure of a highly expanded compressed natural gas (Methane; CH4) spray were studied experimentally and numerically. The spraying characteristics and shockwave structures were analyzed, showing that increasing the injection pressure did not improve the spray tip penetration but increased the choking phenomenon. This phenomenon is a key factor that affects the shockwave structure and leads to an increase in the spray volume and area.
Article
Thermodynamics
Mengzhao Chang, Suhan Park
Summary: The main purpose of this study is to predict the characteristics of flash boiling spray using a machine learning model, and further analyze the characteristics. Three decision tree algorithms and the tree-structured parzen estimator were used to build the models. The study found that the injection conditions have a greater influence on the spray characteristics.
Article
Energy & Fuels
Seongin Jo, Hyung Jun Kim, Sang Il Kwon, Jong Tae Lee, Suhan Park
Summary: Passenger cars are the largest contributor to GHG emissions in the road sector, but heavy-duty vehicles account for about a quarter of emissions despite their smaller numbers. Therefore, it is important to improve the fuel efficiency of heavy-duty vehicles in order to reduce CO2 emissions. In this study, a simulation was used to analyze the effects of payload, air drag coefficient, and rolling resistance on fuel economy, CO2 emission, and the valid window ratio for three driving routes. The results showed that at higher vehicle speeds, the air drag coefficient had a greater impact on fuel economy, while reducing rolling resistance had a greater impact at lower speeds.
Article
Thermodynamics
Mengzhao Chang, Huijun Kim, Bo Zhou, Suhan Park
Summary: The purpose of this study was to compare the spray collapse resistance of GDI injectors with different hole structures. A shadowgraph visualization system and MATLAB were used to record and analyze the spray characteristics. The impact of hole length-to-diameter (L/D), hole shape, and step hole diameter (Ds) on spray collapse were quantitatively analyzed. Furthermore, CFD simulation was conducted to explore the spray collapse mechanism. Results showed that the step hole diameter had the greatest influence on the spray collapse point, with a smaller diameter delaying the collapse point by approximately 22 degrees C.
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.