Article
Thermodynamics
Yimeng Wu, Haihao Qin, Zijian Zhang, Lei Zhou
Summary: This study investigated the soot primary particle size in n-heptane\air diffusion flame at pressures up to 5 bar using TiRe-LII technique, revealing an increase in soot primary particle size with enhancing laser fluence and the significant impact of pressure on the spatial distribution of particle size.
COMBUSTION AND FLAME
(2022)
Article
Thermodynamics
Hafiz M. F. Amin, William L. Roberts
Summary: The study found that soot emissions from diesel engines and gas turbines are influenced by combustion environment factors such as pressure. Using two angle light scattering and extinction technique, soot parameters during combustion could be measured, including soot volume fraction and primary particle size.
COMBUSTION SCIENCE AND TECHNOLOGY
(2021)
Article
Energy & Fuels
Yu Cai, Zijian Zhang, Lei Zhou
Summary: This study investigated the formation of PAHs and soot in flames at elevated pressures. The results showed that with the increase of pressure, flame stability becomes worse and both soot and PAHs concentrations are increased. Additionally, a linear correlation was found between Soot-LII and PAHs-LIF, with varying slopes at different laser energies.
Article
Thermodynamics
Junjun Guo, Hong G. Im
Summary: Detailed numerical simulations were conducted on C2H4/Air coflow laminar sooting flames at atmospheric and elevated pressures. The simulations included fully coupled flow, gas-phase reactions, soot dynamics, and non-gray radiative heat transfer. Different radiation models were compared to study their effect on predictions. The results showed that the DOM combined with the WSGG-SK model provided consistent predictions with the FSCK model, with errors less than 2%.
COMBUSTION SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Applied
Xiaokang Nie, Jiawei Qi, Shunjie Feng, Ya Liu, Bingbing Qiu, Huaqiang Chu
Summary: In this study, the mixture of n-heptane and toluene was used as a surrogate fuel for diesel. The flame morphology, particle size, and soot deposition of three kinds of fuel blends were investigated using various microscopy techniques. The results showed that the addition of toluene promoted the formation of soot and influenced its morphology and structure.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Chemistry, Applied
Xiaokang Nie, Jiawei Qi, Shunjie Feng, Ya Liu, Bingbing Qiu, Huaqiang Chu
Summary: This study investigated the particle size, nanostructure, microcrystalline size, and soot deposition morphology of three different fuel laminar diffusion flames of n-heptane and toluene blends using TEM, HRTEM, XRD, and FESEM. Results showed that with an increase in toluene content, flame height increased, temperature decreased, PAH content increased, promoting soot formation with larger particle size. Additionally, the graphitization degree of soot increased with toluene content, leading to larger fringe length and microcrystalline width.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Thermodynamics
Francisco Cepeda, Rodrigo Demarco, Felipe Escudero, Juan Jose Cruz Villanueva, Gonzalo Carvajal, Andres Fuentes
Summary: This study investigated the relationship between soot concentration and temperature, and provided new data for time-dependent numerical simulations by measuring local radiative heat flux on transient laminar flames. Results showed that forced condition significantly changed soot production, temperature distribution, and radiative properties, enhancing flame radiation.
COMBUSTION AND FLAME
(2022)
Article
Energy & Fuels
Yang Liu, Yishu Xu, Kai Zhang, Pu Zhang, Xiaobei Cheng
Summary: In this study, the effects of NH3 addition on the morphology and nanostructures of soot particles in ethylene co-flow diffusion flames were investigated. The results showed that NH3 addition resulted in changes in flame height and temperature, as well as a decrease in the size and number of soot particles. The investigation of soot nanostructures indicated that NH3 delayed the process of particle inception and surface growth.
Article
Energy & Fuels
Shunjie Feng, Run Hong, Jiawei Qi, Wenlong Dong, Bingbing Qiu, Xianyao Yan, Huaqiang Chu
Summary: The influence of ammonia on the morphology of soot and the evolution of nanoparticle structure in the laminar flame of ethylene was studied. The experimental results showed that the addition of ammonia can inhibit the growth of soot nuclei and delay the formation of incipient soot, and has different effects on the evolution of soot morphology and structure in the ethylene flame. The main reason may be the chemical and thermal effects of ammonia on the nanostructure and morphology of soot at different stages of soot formation.
Article
Thermodynamics
Peng Liu, Hafiz Ahmad, Xuesong Jiang, Hongyu Chen, Yan Lin, Bowen Mei, Yuyang Li
Summary: This study investigated the structure and oxidation reactivity of soot sampled from an ethylene flame, showing that residence time is crucial in modifying surface functional groups and that as soot matures, the oxidation reaction transitions into a unimodal process.
COMBUSTION AND FLAME
(2021)
Article
Thermodynamics
Mingyan Gu, Fengshan Liu, Jean-Louis Consalvi, Omer L. Gulder
Summary: This study numerically investigated the soot formation in flames fueled with liquid hydrocarbons at elevated pressures, finding that pressure has a significant impact on soot production, with an increase in pressure enhancing the soot formation process, particularly PAH condensation.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Thermodynamics
Carson Chu, Ali Naseri, Tirthankar Mitra, Mehran Dadsetan, Anton Sediako, Murray J. Thomson
Summary: Experimental investigation reveals that increasing reactant temperature promotes soot formation, aggregation, and larger primary particle size. However, there is a deceleration in soot surface growth at certain temperatures, suggesting the presence of surface aging effects.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Thermodynamics
Francisco Cepeda, Luke Di Liddo, Marek Serwin, Ahmet E. Karatas, Seth B. Dworkin
Summary: This study investigates the effects of adding oxygen to laminar co-flow DME diffusion flames, and reveals a reversal phenomenon in soot production. The chemical effects of adding oxygen are found to be more important than the thermal and dilution effects. It is concluded that the reversal occurs when nearly all DME disassociated before exiting the fuel tube, indicating a sudden transition from a partially premixed DME flame to one which primarily burns C1 fuel fragments. This study provides important insights into the control mechanisms of soot production in DME combustion.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Marek Serwin, Ahmet E. Karatas
Summary: The experimental study evaluated the soot volume fractions of binary mixtures of ethane, DME, and oxygen in a co-flow burner. It was found that increasing oxygen content decreased flame heights but had complex and sometimes unexpected effects on soot formation. The addition of oxygen could lead to sudden reversals in the impact on soot formation, making the behavior nonmonotonic.
COMBUSTION AND FLAME
(2021)
Article
Crystallography
Hiroshi Sakurai, Naruki Tsuji, Yoshio Zama, Kosuke Suzuki, Kazushi Hoshi, Daisuke Hiramoto, Yoshiharu Sakurai, Tomohiko Furuhata
Summary: X-ray Compton scattering was used to measure the temperature distribution and chemical state distribution of a laminar diffusion flame, showing its potential as a novel nondestructive measurement method for temperature and chemical states in combustion reactions.
Article
Chemistry, Physical
Shina Maini, Cheolhee Shin, John Z. Wen, Boyu Li, Anton Sediako, Murray J. Thomson
Summary: This study experimentally determined the chemical reaction parameters for ceria nanoparticle-catalyzed soot oxidation and investigated the effects of gas diffusion and the contact area on the reaction rate.
APPLIED CATALYSIS A-GENERAL
(2022)
Article
Thermodynamics
Neil A. Juan, Nick A. Eaves, Murray J. Thomson
Summary: This study examines two-dimensional effects in nanoparticle formation using both a 2D model and a simplified 1D model in laminar flow reactors. The findings suggest that the simplified 1D model can achieve comparable accuracy in predicting particle formation processes to the 2D model, with lower computational costs. Both models perform similarly in predicting gas-phase species and can adequately capture particle characteristics such as volume fraction, number densities, and size distributions.
COMBUSTION AND FLAME
(2022)
Article
Thermodynamics
Mohsen Broumand, Muhammad Shahzeb Khan, Sean Yun, Zekai Hong, Murray J. Thomson
Summary: An aqueous surrogate was developed for spray evaluation of viscous bioliquids, mimicking the physical properties of fast pyrolysis bio-oil. Experimental results showed that the surrogate and FPBO exhibited similar rheological characteristics and spray performances.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2021)
Article
Mechanics
Mohsen Broumand, Muhammad Shahzeb Khan, Harshavardhan Kuppili, Sean Yun, Zekai Hong, Murray J. Thomson
Summary: This study investigates the influence of preheating temperature on the atomization of a high-viscosity fluid, FPBO. The rheological properties of FPBO were determined at different temperatures and used to analyze its flow structures and spray characteristics. The results show that a higher preheating temperature leads to a narrower size distribution and smaller mean diameter of spray droplets.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2022)
Article
Mechanics
M. Broumand, A. Asgarian, M. Bussmann, K. Chattopadhyay, M. J. Thomson
Summary: The study investigates the dynamic behavior and disintegration mechanisms of a fan liquid sheet under different injection pressures, and proposes a model based on linear stability analysis to predict the characteristics of the liquid sheet. The experimental and analytical results are consistent, providing an effective method for estimating droplet diameter.
Article
Chemistry, Physical
Dhanya Puthusseri, Mehran Dadsetan, Zhimin Qi, Ali Naseri, Haiyan Wang, Murray J. Thomson, Vilas G. Pol
Summary: The thermal decomposition mechanism of a Li-rich rock salt cathode material Li1.3Mn0.4Nb0.3O2 was studied, revealing its poor thermal stability and higher susceptibility to thermal runaway compared to state-of-the-art cathode materials. The reaction between the transition metal and electrolyte was identified as the limiting factor for its thermal stability. These findings address important knowledge gaps and provide insights for improving the safety and performance of Li-ion batteries.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Mehran Dadsetan, Ali Naseri, Murray J. Thomson
Summary: Carbon black oxidation is a post-treatment method that controls its properties for different applications. The study investigates the effect of particle size on oxidation pathway and rate by oxidizing three different sizes of carbon blacks. The diffusion-controlled burning model is validated for all samples oxidized at 800 degrees C in the presence of oxygen molecules. Under electron-beam irradiation, larger particles show a reduction in oxidation rate due to the breaking of atomic bonds and transformation to the graphitic structure. However, surface burning remains the dominant mode under electron-beam irradiation.
Article
Thermodynamics
Ali J. Naseri, M. Reza Kholghy, Neil A. Juan, Murray J. Thomson
Summary: In this study, a sectional population balance model (SPBM) coupled with chemistry was used to simulate the formation of carbon black by ethylene pyrolysis. The results show that the reversible dimerization and surface growth model can accurately predict the particle size distribution and morphology.
COMBUSTION AND FLAME
(2022)
Article
Energy & Fuels
Muhammad Shahzeb Khan, Yikai Min, Mohsen Broumand, Sean Yun, Zekai Hong, Murray J. Thomson
Summary: By employing thermo-catalytic reforming bio-oil (TCRBO) process, higher quality bio-oil with advantages in combustion performance, such as higher fuel heating value and lower emissions, was obtained. TCRBO demonstrated better atomization compared to FPBO, resulting in reduced fuel flow rate and lower PM emissions.
Article
Thermodynamics
Carson Chu, Mohammed H. Zaher, Murray J. Thomson
Summary: This study assessed the temperature sensitivity of n-propylbenzene and 1,2,4-trimethylbenzene on soot formation in coflow diffusion flames. The results showed that increasing the temperature led to higher soot volume fractions and primary particle diameters, but alkyl benzenes exhibited lower temperature sensitivity. The model indicated that raising the reactant temperature did not significantly affect the production of soot precursor PAH, but altered the available time for soot growth, promoting soot formation. Furthermore, the impact of fuel temperature on soot formation was more pronounced along the centerline.
COMBUSTION AND FLAME
(2022)
Article
Engineering, Chemical
Neil A. Juan, Ali Naseri, M. Reza Kholghy, Murray J. Thomson
Summary: Flow reactors are commonly used to study nanoparticle formation. This article presents a detailed model called NanoParticle Flow Reactor (NanoPFR), which can simulate nanoparticle synthesis in flow reactors and predict the morphology and size distribution. The model has been validated through experiments.
INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING
(2023)
Article
Engineering, Mechanical
Mohsen Broumand, Murray J. Thomson, Sean Yun, Zekai Hong
Summary: This study focuses on the application of bio-oils in microgas turbines (MGTs). Measurements of spray size and velocity of preheated bio-oil injected from an OEM twin-fluid atomizer at elevated pressures were conducted. The results showed that the cone angle of sprays is insensitive to pressure, but decreases with increasing gas-to-liquid momentum flux ratio. Droplet mean diameters increase and velocities decrease with increasing pressure, due to the effect of gas-to-liquid density ratio. A modified correlation for estimating the Sauter mean diameter of spray droplets was proposed based on gas Weber number, gas-to-liquid momentum flux ratio, density ratio, and viscosity ratio.
JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME
(2022)
Article
Thermodynamics
Arash Khabazipur, Nickolas Eaves
Summary: A new fully reversible PAH clustering model is introduced to understand the clustering behavior and formation of carbon nanoparticles. The model is validated and found to accurately describe the reversible rates of clustering. Efficiency-based models are shown to be inadequate for modeling PAH clustering.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Engineering, Multidisciplinary
Arash Khabazipur, Nick A. Eaves
Summary: This study investigates the differing effects of dilution with H-2 and N-2 on particle inception and surface growth during combustion processes. Dilution with N-2 leads to greater reductions in HACA and PAH adsorption, as well as delays in particle inception and surface growth.
COGENT ENGINEERING
(2022)
Article
Thermodynamics
Yifan Yang, Haodong Zhang, Linye Li, Mingming Gu, Xi Xia, Fei Qi
Summary: This paper investigates the formation of a blue whirl by controlling tangential and radial airflows. By using a unique fire whirl apparatus, the blue whirl can be formed directly upon ignition without going through the transient phase. The study also discovers new flame regimes and explores the mechanism behind the formation and transition of the blue whirl.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Xiaobin Qi, Songyan Gao, Zhiping Zhu, Qinggang Lyu, Haixia Zhang
Summary: This study experimentally investigated the propagation characteristics of reverse combustion under oxygen-limited and enriched conditions. The contribution of volatiles gas-phase oxidation and char surface oxidation to reverse combustion was evaluated. The results showed that oxygen enrichment expanded the operating range of oxygen flow rate for reverse combustion and enhanced the low-temperature oxidation of the solid fuel. The findings provide a better understanding of the driving mechanism of reverse combustion and have important implications for efficient thermal conversion of solid fuels.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Bingjie Chen, Peng Liu, Bingzhi Liu, Zhandong Wang, Xiang Gao, William L. Roberts
Summary: In this study, the low temperature oxidation of 1,2,4-trimethylbenzene was investigated using experiments and numerical simulations. The results showed the presence of toxic oxygenated aromatic compounds and proposed potential formation pathways. The numerical simulations accurately predicted the mole fractions of most compounds, but some compounds were missing.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Meng Sui, Zhiheng Zhu, Fashe Li, Hua Wang
Summary: The effect of adding ferrocene as a combustion catalyst to Jatropha biodiesel on its pyrolysis and combustion performance is investigated. The results show that adding ferrocene reduces activation energy and harmful emissions while improving combustion efficiency.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Manaf Sheyyab, Mohammed Abdulrahman, Subharaj Hossain, Patrick T. Lynch, Eric K. Mayhew, Kenneth Brezinsky
Summary: Fuel surrogates, simplified representations of complex fuels, accurately model speciation results and reaction kinetics, reproduce the ignition quality and chemical functional group compositions of their parent fuels.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Yan Wang, Shumeng Xie, Hannes Bottler, Yiqing Wang, Xinyi Chen, Arne Scholtissek, Christian Hasse, Zheng Chen
Summary: This study investigates how flow affects the ignition and transition process of a cool flame. The results show that the ignition energy determines the highest temperature and the strain rate influences the flame propagation and the transition from cool flame to hot flame.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Tanusree Chatterjee, Mengyuan Wang, Goutham Kukkadapu, Chih-Jen Sung, William J. Pitz
Summary: Cycloalkanes, including cyclohexane, are important hydrocarbons in transportation fuels. However, limited oxidation data at low-to-intermediate temperatures and inadequate predictive ability of kinetic models have hindered the understanding and improvement of cyclohexane oxidation. This study provides experimental and modeling results to develop a more accurate kinetic model for cyclohexane oxidation.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Tao Wu, Erik Hagen, Haiyang Wang, Dylan J. Kline, Michael R. Zachariah, Carole Rossi
Summary: It was found that incorporating CuO into Al/I2O5 can significantly reduce the ignition time and enhance the combustion performance. The optimum composition of 80/20 wt% of I2O5/CuO shows a 30 times shorter ignition time and produces a peak pressure and pressurization rate 4 and 26 times greater than traditional Al/I2O5. A series of characterizations helped unravel the cause of improvement and propose a reaction mechanism for this ternary Al/I2O5/CuO system. This study proposes a facile, inexpensive, and efficient way to enhance the combustion performance of Al/I2O5 biocidal nanoenergetic materials.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Mahmoud Gadalla, Shervin Karimkashi, Islam Kabil, Ossi Kaario, Tianfeng Lu, Ville Vuorinen
Summary: In this study, the flame initiation process in dual-fuel spray assisted combustion is explored through scale-resolved simulations, providing numerical evidence on the initiation of premixed flames. It is found that there is a transient mixed-mode combustion phase after ignition, followed by a primarily deflagrative combustion mode. The interactions between turbulence and premixed flame front are characterized in the corrugated regime.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Neeraj Kumar Pradhan, Arindrajit Chowdhury, Debasis Chakraborty, Neeraj Kumbhakarna
Summary: In this study, a modified model for predicting the burn rate of composite solid propellants is proposed. The model has been validated against experimental and theoretical results, and it outperforms existing models in all cases considered. The model is highly robust and provides results quickly, making it highly efficient in terms of time, effort, and computational resources.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Lili Ye, Zhihe Zhang, Fan Wang, Xiaodong Wang, Yiming Lu, Lei Zhang
Summary: This study investigated the pyrolysis mechanism of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) explosive using ab initio and kinetic modeling simulations. The results showed that N-NO2 bond fission and C-H beta-scission are important channels in the decomposition of HMX.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Andrei N. Lipatnikov, Hsuchew Lee, Peng Dai, Minping Wan, Vladimir A. Sabelnikov
Summary: This study investigates the importance of thermodiffusive and hydrodynamic instabilities of laminar flames in turbulent flows through numerical simulations. The analysis suggests that laminar flame instabilities play a minor role at sufficiently high Karlovitz numbers.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Shijie Xu, Yue Qiu, Leilei Xu, Jianqing Huang, Shen Li, Elna J. K. Nilsson, Zhongshan Li, Weiwei Cai, Marcus Alden, Xue-Song Bai
Summary: Metal powder is a promising carbon-free and recyclable energy carrier. In this study, a computational model for the combustion and phase change of micron-sized iron particles was proposed and validated. The model successfully captures the melting, surface reactions, cooling, and solidification processes. The study also reveals a two-stage solidification phenomenon and identifies a diffusion-controlled mechanism during the melting process. The reaction between iron and CH4/O2/N2 flame products is found to play a significant role in the iron combustion process.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Khalid Aljohani, Abd El-Sabor Mohamed, Haitao Lu, Henry J. Curran, S. Mani Sarathy, Aamir Farooq
Summary: This study investigates the impact of exhaust gas recirculation (EGR) and NOx on the ignition delay time of oxygenated gasoline. A gasoline surrogate model is developed and the experimental data are useful for predicting fuel ignition behavior in internal combustion engines. The results show that EGR inhibits gasoline reactivity, while NOx has a promoting effect at high temperatures. This research is important for understanding the combustion behavior of gasoline in engines.
COMBUSTION AND FLAME
(2024)
Article
Thermodynamics
Chengcheng Ao, Jia Yan, Tong Yan, Lidong Zhang, Pan Wang
Summary: This study investigates the inhibitory effect of ammonia blended with hydrocarbon fuels on soot formation. The results show that there is a chemical interaction between ammonia and polycyclic aromatic hydrocarbons (PAHs), blocking the formation of larger PAHs.
COMBUSTION AND FLAME
(2024)
