Article
Energy & Fuels
Hamed Karimi Motaalegh Mahalegi, Amir Mardani
Summary: In this study, a numerical examination is conducted on the experimental MILD turbulent spray burner of Delft Spray in Hot Co-flow, DSHC. The structure of the triple-flame of liquid fuel in the atmospheric condition is found to be different from the conventional gaseous triple-flames. The sensitivity analysis relative to the temperature and oxygen concentration of the co-flow stream is performed independently.
Article
Thermodynamics
Douglas B. Proud, Michael J. Evans, Qing N. Chan, Paul R. Medwell
Summary: This study investigates the structure and stabilisation mechanisms of ethanol and n-heptane spray flames using laser diagnostic techniques. The results show a noticeable shift in flame stabilisation behavior with variations in coflow oxygen concentration, while coflow temperature does not seem to have a significant impact. These flames exhibit interesting deviations from typical behaviors observed in gaseous and prevaporised flames in similar configurations, especially for coflow conditions associated with the transition to the mild combustion regime.
COMBUSTION AND FLAME
(2022)
Article
Chemistry, Applied
Xiaoteng Zhang, Chao Geng, Zhenyang Ming, Haifeng Liu, Yanqing Cui, Chao Jin, Long Liu
Summary: This paper studies the combustion characteristics of pure ethanol spray flame and compares it with methanol and n-butanol. The results show that the ethanol spray flame exhibits an unstable yellow flame, and the flame brightness, soot concentration, and ignition delay increase with the increase of injection mass. Increased injection pressure leads to an increase in the soot lift-off length and a decrease in flame brightness, but has a negligible effect on reducing ignition delay.
FUEL PROCESSING TECHNOLOGY
(2023)
Article
Energy & Fuels
Jingjing He, Xin Su, Hao Chen, Yisong Chen, Xinfeng Zhang, Yanfang Liu, Zhilin Tian, Hongming Xu
Summary: This study investigates the spray and combustion characteristics of diesel blends with different PODE blending ratios. The results show that adding PODE can significantly reduce soot emissions. The higher the PODE blending ratio, the less soot formation.
Article
Energy & Fuels
Qiankun Zhang, Jin Xia, Jianping Wang, Zhuoyao He, Yong Qian, Xingcai Lu
Summary: The study aims to explore the spray and combustion characteristics of collision biodiesel and butanol under different collision angles, injection pressures, and ambient conditions. The results show that the spray in the horizontal direction has faster evaporation and diffusion rates compared to the vertical direction. Increasing the ambient temperature has a positive impact on promoting the horizontal diffusion of the vapor-phase spray. At larger collision angles, higher relative velocity leads to a more intense collision process and smaller diffusion rate after the collision. A smaller equivalence ratio after the collision leads to longer ignition delay and shorter flame lift-off length, contributing to a more intense combustion process and higher soot emissions. Increasing the injection pressure can improve the ignition and combustion characteristics, except at larger collision angles where the reduction in soot emissions is suppressed.
Article
Thermodynamics
Mohammad Zandie, Hoon Kiat Ng, Suyin Gan, Mohd Farid Muhamad Said, Xinwei Cheng
Summary: This research analyzes the combustion, soot formation, and exhaust emissions of diesel, biodiesel, gasoline fuels, and their mixtures in a constant volume chamber. The study focuses on the effects of different ambient temperature and oxygen levels on flame structure and emissions. The results show that the mixture D65 | BD20 | G15 has lower soot formation and nitrogen oxide emissions. Lowering the ambient temperature and increasing the oxygen concentration further reduce the emissions.
Article
Energy & Fuels
Ying Wang, Peng Wang
Summary: This study investigates the influence of premixed hydrous ethanol on diesel combustion and soot production. The results showed that a premixed atmosphere can inhibit the combustion of n-heptane spray. A rise in water content and ethanol premixed equivalence ratio increased the ignition delay time and flame lift off length, while reducing soot generation. Additionally, a decrease in ambient oxygen concentration extended the ignition delay time and flame lift off length, resulting in reduced soot production. However, when the initial ambient temperature was high, the combustion of hydrous ethanol enhanced the charge temperature and counteracted the combustion delay effect caused by the premixed atmosphere.
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Energy & Fuels
Qing Cao, Dingjiang Xie, Kuanyu Wang, Ningfei Wang, Baolu Shi
Summary: This study proposes a compact dual swirl combustor to establish a steady liquid ethanol tubular flame. By enhancing the heat transfer process and promoting reactant mixing, the overall heat output approaches 10 kW, much higher than the original combustor. With an increase in inner air flow rate, flame anchoring and soot formation can occur.
Article
Environmental Sciences
Shengbo Ge, Arivalagan Pugazhendhi, Manigandan Sekar, Changlei Xia, Ashraf Elfasakhany, Kathirvel Brindhadevi, Kanda Whangchai
Summary: The study demonstrates that using Schizochytrium microalgae bio-oil as biofuel for diesel engines shows improved performance in terms of fuel efficiency and reduced harmful gas emissions, except for NOX which is slightly higher than diesel. Overall, the differences between them are negligible.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Energy & Fuels
S. Manigandan, P. Gunasekar, T. R. Praveenkumar, Jamal S. M. Sabir, Thangavel Mathimani, Arivalagan Pugazhendhi, Kathirvel Brindhadevi
Summary: An experimental study was conducted to determine the performance, noise, and emission characteristics of a two-cylinder diesel engine powered by Canola and Moringa oleifera blends. The study found that Moringa oleifera exhibited superior performance compared to canola blends, and the addition of multi-walled carbon nanotubes improved combustion and performance characteristics of the diesel engine.
Article
Energy & Fuels
Shengbo Ge, Kathirvel Brindhadevi, Changlei Xia, Amany Salah Khalifa, Ashraf Elfasakhany, Yuwalee Unpaprom, Hien Van Doan
Summary: The study focused on improving the performance and emulsion characteristics of biodiesel extracted from spirulina microalgae by adding a small dosage of Al2O3 nanoparticles as a catalyst. The results showed that the nanoparticles added to biodiesel reduced harmful gas emissions, improved combustion quality, and increased fuel efficiency compared to pure diesel blends.
Article
Energy & Fuels
Limin Geng, Leichao Bi, Qi Li, Hao Chen, Yuantao Xie
Summary: The study found that adding ethanol to biodiesel improves spray characteristics and combustion performance in diesel engines. At low loads, peak cylinder pressures (PCPs) of BE blends are higher than diesel, while peak heat release rates (PHRRs) are also higher. However, at medium-high loads, PHRRs decrease and emissions decrease with increasing ethanol blending ratio.
Article
Energy & Fuels
Gang Li, Jiayi Dai, Zhien Liu, Timothy H. Lee, Chunhua Zhang
Summary: This study investigated the spray, combustion, and flame characteristics of n-hexanol/diesel blends using optical diagnostics. Results showed that blending n-hexanol into diesel improved spray characteristics, decreased combustion pressure slightly, shortened combustion duration, increased flame lift-off length, and reduced spatial integrated natural luminosity peaks.
Article
Energy & Fuels
Enrico R. Malheiro de Oliveira, Caio Henrique Rufino, Pedro Teixeira Lacava
Summary: This study provides an experimental analysis of spray guided direct injection with commercial fuels used in a consolidated market for the use of ethanol. The results indicate that lean combustion can lead to flame instabilities, increased unburned ethanol in exhaust emissions, and reduced engine performance. The study highlights the importance of considering the effects of commercial fuels with high ethanol content on engine performance and emissions.
Article
Energy & Fuels
M. Mubarak, A. Shaija, T. V. Suchithra
Summary: Experimental results show that using Salvinia molesta biodiesel blend as fuel in diesel engines can significantly reduce peak pressure and heat release rate, as well as improve performance and reduce emissions, with B20 blend performing the best.
Article
Optics
Timothy Y. Chen, Ning Liu, Christopher J. Kliewer, Arthur Dogariu, Egemen Kolemen, Yiguang Ju
Summary: We report the development of a simple and sensitive two-beam hybrid femtosecond/picosecond pure rotational coherent anti-Stokes Raman scattering (fs/ps CARS) method to simultaneously measure the rotational and vibrational temperatures of diatomic molecules. This method utilizes coherence beating effects to infer the temperatures and a model for extraction. The experimental results are in good agreement with the model.
Article
Chemistry, Physical
Hao Zhao, Guohui Song, Zhe Chen, Xiaofang Yang, Chao Yan, Shota Abe, Yiguang Ju, Sankaran Sundaresan, Bruce E. Koel
Summary: Ammonia synthesis at 533 K and atmospheric pressure was investigated in a plasma reactor without packing and with catalyst particles. Gas-phase species NNH and N2H2 were identified and their importance in plasma-assisted ammonia synthesis was demonstrated. The study showed the significance of in situ identification of gas-phase species for studying the kinetics of plasma-assisted catalysis.
ACS ENERGY LETTERS
(2022)
Article
Physics, Applied
Ning Liu, Timothy Y. Chen, Hongtao Zhong, Ying Lin, Ziyu Wang, Yiguang Ju
Summary: This Letter reports a femtosecond ultraviolet laser absorption spectroscopy (fs-UV-LAS) technique for simultaneous in situ measurements of temperature and species. The fs-UV-LAS technique has three major diagnostic benefits, including simultaneous multi-parameter measurements with enhanced accuracy, ultrafast time resolution, and the ability to measure in plasmas with low OH number density and in flames with single-shot absorption measurements.
APPLIED PHYSICS LETTERS
(2022)
Article
Thermodynamics
Minhyeng Kim, Kendyl A. Waddell, Peter B. Sunderland, Vedha Nayagam, Dennis P. Stocker, Daniel L. Dietrich, Yiguang Ju, Forman A. Williams, Phillip Irace, Richard L. Axelbaum
Summary: An improved understanding of cool diffusion flames, investigated in the microgravity environment of the International Space Station using a spherical porous burner, has the potential to enhance engine performance. The experiments included various fuel and oxygen concentrations, pressures, and flow rates, and utilized diagnostics such as intensified video cameras, radiometers, and thermocouples. The results revealed the presence of spherical cool diffusion flames, with particular conditions required for their production, and highlighted the significance of burner temperature and rich regions near a mixture fraction of 0.53.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Xingqian Mao, Hongtao Zhong, Ziyu Wang, Timothy Ombrello, Yiguang Ju
Summary: This study numerically investigates the effects of non-equilibrium nanosecond plasma discharge on the critical ignition volume, minimum ignition energy, and chemistry in a plasma-assisted H2/air flow. It examines the interactions between discharges/ignition kernels in different regimes and analyzes the impact of flow velocity and pulse number on ignition enhancement. The findings reveal that flow velocity increases the minimum ignition energy and that the minimum critical ignition volume decreases with the increase of plasma discharge energy. Sequential two-pulse discharges show ignition failure in certain regimes but succeed in the fully-coupled regime at a shorter inter-pulse time. The study also demonstrates that an optimal pulse repetition frequency and pulse number can achieve effective ignition enhancement.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Christopher B. Reuter, Ziyu Wang, Wenbin Xu, Yiguang Ju
Summary: This investigation examines the effectiveness of flame suppressants on both hot flames and cool flames. It is found that chemically based suppressants are less effective on cool flames compared to hot flames, and some mildly flammable suppressants can ignite under cool flame conditions. Detailed analysis reveals that the reaction rates interfering with radical production are much lower in cool flames. This premature oxidation phenomenon is not predicted by kinetic models.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Ziyu Wang, Hao Zhao, Chao Yan, Ying Lin, Aditya D. Lele, Wenbin Xu, Brandon Rotavera, Ahren W. Jasper, Stephen J. Klippenstein, Yiguang Ju
Summary: Methanol oxidation was studied in a supercritical pressure jet-stirred reactor. It was found that the onset temperature of methanol oxidation at 100 atm is lower than that at 10 atm and a negative temperature coefficient (NTC) behavior was observed at fuel-rich conditions. The kinetics models failed to predict these trends accurately. By updating elementary reaction rates and adding new reaction pathways, the model improved but discrepancies still exist.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Tianhan Zhang, Adam J. Susa, Ronald K. Hanson, Yiguang Ju
Summary: This study investigates the initiation, propagation, and transition of spherical cool and double flames induced by laser ignition using a detailed mechanism simulation. The results show that the laser ignition generates vortex pairs that distort the temperature field and distribution of radicals. The laser-ignited hot flame can transition to a cool flame or a transient premixed double flame depending on the laser pulse energy.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Christopher M. Burger, Nils Hansen, Angie J. Zhang, Yiguang Ju
Summary: The low-temperature oxidation of methane by CuO using a coaxial, fixed bed, double dielectric barrier discharge (DBD) reactor was investigated. The experiment showed that plasma conditions significantly enhanced fuel oxidation and CO2 production at lower temperatures (≤600°C) compared to non-plasma conditions.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Hao Zhao, Chao Yan, Guohui Song, Ziyu Wang, Yiguang Ju
Summary: The low and intermediate temperature oxidation of propane was studied in a supercritical pressure jet stirred reactor (SP-JSR) under different conditions. The experiment found a weak negative temperature coefficient (NTC) behavior at 100 atm due to the shift of intermediate temperature HO2 chemistry to lower temperature. Existing literature models could capture the onset temperatures of low and intermediate chemistry, but failed to predict the fuel oxidation quantitatively and capture the NTC behavior. This highlights the uncertainties in developing hierarchy models for fuels with low temperature chemistries at extremely high pressures.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Chemistry, Physical
Christopher M. Burger, Angie J. Zhang, Yijie Xu, Nils Hansen, Yiguang Ju
Summary: The chemical reaction network of low-temperature plasma-assisted oxidation of methane and ethylene with nickel oxide was studied using electron-ionization molecular beam mass spectrometry. Plasma significantly enhanced methane oxidation between 400 and 500 degrees C, while no oxidation was observed without plasma. Different oxidation stages were observed for methane at higher temperatures. Ethylene experiments showed the formation of new intermediate oxygenated species under plasma conditions. Carbon deposits were observed in both methane and ethylene conditions. A reaction pathway analysis was created based on experimental observations and simulations.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Physical
Ziyu Wang, Chao Yan, Bowen Mei, Ying Lin, Yiguang Ju
Summary: This study investigates the oxidation of diethyl ether (DEE) under low-temperature and ultra-high-pressure conditions. The experimental data shows that DEE exhibits unusual low-temperature oxidation behavior with two negative temperature coefficient (NTC) zones. Increasing the pressure stabilizes RO2 and promotes HO2 chemistry, resulting in weaker NTC zones. The existing DEE model is updated to improve the predictability of key species, especially at intermediate temperature.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Thermodynamics
Long Zhu, Qiang Xu, Bingzhi Liu, Cheng Xie, Yanbo Li, Hong Wang, Hao Lou, Qingbo Zhu, Snehasish Panigrahy, Henry Curran, Ziyu Wang, Yiguang Ju, Zhandong Wang
Summary: This paper investigated the ozone-initiated low-temperature oxidation of methane and ethane and identified numerous oxygenated species as the products. The study revealed that the reaction mechanism of alkylperoxy radicals is crucial in accurately predicting the low-temperature oxidation chemistry of methane and ethane. The results highlight the need for further research on the key intermediates in the base model for chemically sensitized low-temperature fuel oxidation.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Madeline Vorenkamp, Scott A. Steinmetz, Timothy Y. Chen, Xingqian Mao, Andrey Starikovskiy, Christopher Kliewer, Yiguang Ju
Summary: This study investigates the effect of nanosecond dielectric barrier discharge (ns-DBD) plasma on deflagration to detonation transition (DDT) in a microchannel with a fuel-lean, DME, oxygen, and argon premixture. The results show that the plasma discharge can nonlinearly affect the onset time and distance of DDT. By adjusting the number of discharge pulses, DDT can be controlled. This research is of great importance for improving advanced propulsion engines.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Energy & Fuels
Aditya Dilip Lele, Yiguang Ju
Summary: This study introduces a reaction molecular dynamics-based method to examine the pyrolysis chemistry and species timescales, and evaluates the impact of mass residence time distribution (RTD) on product selectivity and yield. Reactive molecular dynamics simulations for polypropylene pyrolysis were conducted with different RTDs, and it was found that RTD and reaction chemistry control the peak non-equilibrium product concentrations. Additionally, product selectivity is strongly affected by average residence time and RTD.
Article
Thermodynamics
Yong Cheng, Fukai Song, Lei Fu, Saishuai Dai, Zhiming Yuan, Atilla Incecik
Summary: This paper investigates the accessibility of wave energy absorption by a dual-pontoon floating breakwater integrated with hybrid-type wave energy converters (WECs) and proposes a hydraulic-pneumatic complementary energy extraction method. The performance of the system is validated through experiments and comparative analysis.
Article
Thermodynamics
Jing Gao, Chao Wang, Zhanwu Wang, Jin Lin, Runkai Zhang, Xin Wu, Guangyin Xu, Zhenfeng Wang
Summary: This study aims to establish a new integrated method for biomass cogeneration project site selection, with a focus on the application of the model in Henan Province. By integrating Geographic Information System and Multiple Criterion Decision Making methods, the study conducts site selection in two stages, providing a theoretical reference for the construction of biomass cogeneration projects.
Article
Thermodynamics
Mert Temiz, Ibrahim Dincer
Summary: The current study presents a hybrid small modular nuclear reactor and solar-based system for sustainable communities, integrating floating and bifacial photovoltaic arrays with a small modular reactor. The system efficiently generates power, hydrogen, ammonia, freshwater, and heat for residential, agricultural, and aquaculture facilities. Thermodynamic analysis shows high energy and exergy efficiencies, as well as large-scale ammonia production meeting the needs of metropolitan areas. The hybridization of nuclear and solar technologies offers advantages of reliability, environmental friendliness, and cost efficiency compared to renewable-alone and fossil-based systems.
Editorial Material
Thermodynamics
Wojciech Stanek, Wojciech Adamczyk
Article
Thermodynamics
Desheng Xu, Yanfeng Li, Tianmei Du, Hua Zhong, Youbo Huang, Lei Li, Xiangling Duanmu
Summary: This study investigates the optimization of hybrid mechanical-natural ventilation for smoke control in complex metro stations. The results show that atrium fires are more significantly impacted by outdoor temperature variations compared to concourse/platform fires. The gathered high-temperature smoke inside the atrium can reach up to 900 K under a 5 MW train fire energy release. The findings provide crucial engineering insights into integrating weather data and adaptable ventilation protocols for smoke prevention/mitigation.
Article
Thermodynamics
Da Guo, Heping Xie, Mingzhong Gao, Jianan Li, Zhiqiang He, Ling Chen, Cong Li, Le Zhao, Dingming Wang, Yiwei Zhang, Xin Fang, Guikang Liu, Zhongya Zhou, Lin Dai
Summary: This study proposes a new in-situ pressure-preserved coring tool and elaborates its pressure-preserving mechanism. The experimental and field test results demonstrate that this tool has a high pressure-preservation capability and can maintain a stable pressure in deep wells. This study provides a theoretical framework and design standards for the development of similar technologies.
Article
Thermodynamics
Aolin Lai, Qunwei Wang
Summary: This study assesses the impact of China's de-capacity policy on renewable energy development efficiency (REDE) using the Global-MSBM model and the difference-in-differences method. The findings indicate that the policy significantly enhances REDE, promoting technological advancements and marketization. Moreover, regions with stricter environmental regulations experience a higher impact.
Article
Thermodynamics
Mostafa Ghasemi, Hegazy Rezk
Summary: This study utilizes fuzzy modeling and optimization to enhance the performance of microbial fuel cells (MFCs). By simulating and analyzing experimental data sets, the ideal parameter values for increasing power density, COD elimination, and coulombic efficiency were determined. The results demonstrate that the fuzzy model and optimization methods can significantly improve the performance of MFCs.
Article
Thermodynamics
Zhang Ruan, Lianzhong Huang, Kai Wang, Ranqi Ma, Zhongyi Wang, Rui Zhang, Haoyang Zhao, Cong Wang
Summary: This paper proposes a grey box model for fuel consumption prediction of wing-diesel hybrid vessels based on feature construction. By using both parallel and series grey box modeling methods and six machine learning algorithms, twelve combinations of prediction models are established. A feature construction method based on the aerodynamic performance of the wing and the energy relationship of the hybrid system is introduced. The best combination is obtained by considering the root mean square error, and it shows improved accuracy compared to the white box model. The proposed grey box model can accurately predict the daily fuel consumption of wing-diesel hybrid vessels, contributing to operational optimization and the greenization and decarbonization of the shipping industry.
Article
Thermodynamics
Huayi Chang, Nico Heerink, Junbiao Zhang, Ke He
Summary: This study examines the interaction between off-farm employment decisions between couples and household clean energy consumption in rural China, and finds that two-paycheck households are more likely to consume clean energy. The off-farm employment of women is a key factor driving household clean energy consumption to a higher level, with wage-employed wives having a stronger influence on these decisions than self-employed ones.
Article
Thermodynamics
Hanguan Wen, Xiufeng Liu, Ming Yang, Bo Lei, Xu Cheng, Zhe Chen
Summary: Demand-side management is crucial to smart energy systems. This paper proposes a data-driven approach to understand the relationship between energy consumption patterns and household characteristics for better DSM services. The proposed method uses a clustering algorithm to generate optimal customer groups for DSM and a deep learning model for training. The model can predict the possibility of DSM membership for a given household. The results demonstrate the usefulness of weekly energy consumption data and household socio-demographic information for distinguishing consumer groups and the potential for targeted DSM strategies.
Article
Thermodynamics
Xinglan Hou, Xiuping Zhong, Shuaishuai Nie, Yafei Wang, Guigang Tu, Yingrui Ma, Kunyan Liu, Chen Chen
Summary: This study explores the feasibility of utilizing a multi-level horizontal branch well heat recovery system in the Qiabuqia geothermal field. The research systematically investigates the effects of various engineering parameters on production temperature, establishes mathematical models to describe their relationships, and evaluates the economic viability of the system. The findings demonstrate the significant economic feasibility of the multi-level branch well system.
Article
Thermodynamics
Longxin Zhang, Songtao Wang, Site Hu
Summary: This investigation reveals the influence of tip leakage flow on the modern transonic rotor and finds that the increase of tip clearance size leads to a decline in rotor performance. However, an optimal tip clearance size can extend the rotor's stall margin.
Article
Thermodynamics
Kristian Gjoka, Behzad Rismanchi, Robert H. Crawford
Summary: This paper proposes a framework for assessing the performance of 5GDHC systems and demonstrates it through a case study in a university campus in Melbourne, Australia. The results show that 5GDHC systems are a cost-effective and environmentally viable solution in mild climates, and their successful implementation in Australia can create new market opportunities and potential adoption in other countries with similar climatic conditions.
Article
Thermodynamics
Jianwei Li, Guotai Wang, Panpan Yang, Yongshuang Wen, Leian Zhang, Rujun Song, Chengwei Hou
Summary: This study proposes an orientation-adaptive electromagnetic energy harvester by introducing a rotatable bluff body, which allows for self-regulation to cater for changing wind flow direction. Experimental results show that the output power of the energy harvester can be greatly enhanced with increased rotatory inertia of the rotating bluff body, providing a promising solution for harnessing wind-induced vibration energy.
