Article
Energy & Fuels
Dong He, Zhimin Peng, Yanjun Ding
Summary: This study compared the performance of different butane isomers as additives in hydrogen-enriched fuel mixtures through experiments and simulations. The results showed that adding isobutane significantly prolonged ignition delay times compared to n-butane, with differences in CO2 formation pathways at selected time points.
Article
Chemistry, Multidisciplinary
Yuhang Li, Zhonghua Jin, Zhichao Wang, Houzhang Tan, Zixiu Jia, Baochong Cui, Shangkun Zhou, Faqi Bai
Summary: The evaluation and reduction of kinetic models for the cofiring of NH3 and CH4 can guide the application of NH3 and CH4 in industrial equipment. Detailed kinetic models were collected and evaluated, and the best overall performance mechanism was determined. Simplified mechanism with good consistency in predicting burning velocity, species concentration, and ignition delay time was achieved.
Article
Energy & Fuels
James M. Harman-Thomas, Touqeer Anwar Kashif, Kevin J. Hughes, Mohamed Pourkashanian, Aamir Farooq
Summary: Experimental data on ignition delay times (IDTs) of syngas in CO2 diluted conditions were obtained. It was found that the reaction of CO2 and H to form CO and OH caused the separation of H2 and CO ignition, increasing the complexity of determining the IDTs. A method to determine simulated IDTs was proposed for effective comparison with experimental data.
Article
Energy & Fuels
Xin Li, Zhihao Ma, Yifan Jin, Xin Wang, Zhideng Xi, Shiji Hu, Xianglin Chu
Summary: This study aims to investigate the influence of methanol addition on the auto-ignition of ammonia under high temperature and low pressure. The ignition delay times (IDTs) of ammonia/methanol mixtures were studied using a shock tube at different conditions. A simplification model (NH3-M model) was constructed based on the Zhang and FFCM-1 mechanisms, and chemical kinetic analyses were performed. The results showed that the addition of 5% methanol significantly shortened the IDTs of the ammonia/methanol mixtures.
Article
Energy & Fuels
Xin Li, Xianglin Chu, Zhihao Ma, Yifan Jin, Xin Wang, Zhideng Xi, Shiji Hu, Hao Chen
Summary: In this study, the ignition delay times (IDTs) of ammonia/ethanol mixtures with different ethanol fractions were measured and analyzed. The results showed that ethanol had a nonlinear and strong ignition-enhancing effect on the IDT of ammonia. A new ammonia/ethanol model was proposed to predict the experimental results reliably.
Article
Thermodynamics
Wenyu Li, Chun Zou, Hong Yao
Summary: Oxy-fuel combustion techniques are crucial for reducing greenhouse gas emissions in fossil fuel power plants. In this study, ignition delay time data were measured for stoichiometric syngas mixtures with different CO concentrations in the presence of CO2. The CO2 collision efficiency in reaction H+O2(+M)=HO2(+M) showed high sensitivity to model predictions.
COMBUSTION AND FLAME
(2023)
Article
Thermodynamics
Jinhu Liang, Chen Zhao, Ziwen Zhao, Xinhui Wang, Ming-Xu Jia, Quan-De Wang, Yang Zhang, Fengqi Zhao
Summary: This study investigates the high-temperature ignition and pyrolysis characteristics of cyclohexylamine through experimental and kinetic modeling approaches. The results show that the ignition delay times and pyrolysis product distributions of cyclohexylamine are influenced by temperature, pressure, and equivalence ratio. A detailed kinetic mechanism accurately predicts the experimental results. Sensitivity analysis identifies the most sensitive reaction as O2 + H = O + OH, and the abstraction reaction of cyclohexylamine with OH radical also exhibits significant sensitivity coefficients. Reaction path analysis reveals the control role of abstraction reactions in the initial oxidation of cyclohexylamine.
COMBUSTION AND FLAME
(2023)
Article
Thermodynamics
Lingfeng Dai, Yi Yuan, Qianjin Lin, Wenyu Li, Chun Zou, Jiacheng Liu, Jianghui Luo
Summary: The ignition delay times (IDTs) of NH3/DMM mixtures at different DMM blending ratios were measured under specific conditions. A detailed DMM-NH3 model was proposed, which accurately predicted the IDTs and laminar flame speeds of NH3/DMM mixtures. The effects of various reactions, such as prompt NO and reburn reactions, recombination reactions, H-abstraction reactions, and disproportionation reactions, on ignition were discussed in detail.
COMBUSTION AND FLAME
(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
Adam J. Susa, Ronald K. Hanson
Summary: This paper reports simultaneous schlieren and emission imaging through the side wall of a round shock tube for experimental autoignition studies. Autoignition experiments are conducted for non-dilute propane-oxygen-argon mixtures at elevated temperatures and pressures. The results show the importance of experimental design and provide valuable data for understanding autoignition processes.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Damien Nativel, Philipp Niegemann, Juergen Herzler, Mustapha Fikri, Christof Schulz
Summary: The study found that the addition of small amounts of helium in high-pressure shock tube can help mitigate pre-ignition of ethanol under different temperature conditions. The experiments showed good agreement between predictions based on detailed kinetics mechanisms and actual results for spatially homogeneous ignition, but inhomogeneities resulted in a shortening of the ignition delay times. Additionally, high-repetition-rate color imaging technology proved useful in differentiating between various ignition modes.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Energy & Fuels
Yifan Jin, Xin Li, Xin Wang, Zhihao Ma, Xianglin Chu
Summary: The contribution of dimethyl ether (DME) to the ignition delay times (IDTs) of ammonia (NH3) was investigated. The experiments were conducted under different pressure, temperature, equivalence ratio, and NH3/DME mixing ratios. The results showed that the addition of DME decreased the IDTs and promoted the reactivity of NH3. The promoting effect of DME on NH3 ignition was weakened under higher temperature and pressure conditions. An updated mechanism was proposed to explain the promoting effect of DME on NH3 ignition, and the numerical analysis showed that it was primarily due to an increase in the rate of production and concentration of the radical pool, especially the OH radical pool.
Article
Energy & Fuels
Zhongjun Wan, Lei Shi, Dongdong Chen, Ping Li, Changhua Zhang
Summary: In this study, the effects of n-butanol on the auto-ignition of toluene reference fuel have been investigated. It was found that n-butanol promotes the auto-ignition of toluene at high temperatures, but inhibits it at low temperatures. A reliable mechanism for n-butanol/toluene reference fuel has been developed and validated through calculations and experiments. The dominant chain propagating reactions were identified, and an inhibiting reaction at low temperatures was also discovered.
Article
Energy & Fuels
Jinhu Liang, Fei Li, Shutong Cao, Xiaoliang Li, Ming-Xu Jia, Quan-De Wang
Summary: This study presents a comparative experimental and kinetic modeling investigation of high-temperature ignition of three C9H12 fuels. The results provide valuable data and insights into the ignition delay time and chemical kinetics, contributing to the understanding and modeling of alkyl aromatics' combustion chemistry.
Article
Energy & Fuels
Matthew G. Sandberg, Claire M. Gregoire, Darryl J. Mohr, Olivier Mathieu, Eric L. Petersen
Summary: This study investigates the effect of norbornadiene (NBD) as a fuel additive on ignition delay times of hydrogen and methane mixtures. The results show that NBD can significantly decrease the ignition delay time for methane, but dramatically increase it for hydrogen reactions.
Article
Thermodynamics
Andrew J. Tykol, F. A. Rodriguez, J. C. Thomas, E. L. Petersen
Summary: This study evaluated the effects of nano- and micro-sized metal oxides on the combustion of automotive airbag gas generant systems, with micro-ceria observed as the only additive that enhanced the burning rate.
COMBUSTION SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Aerospace
James C. Thomas, Eric L. Petersen
Summary: A survey of literature and thermochemical databases revealed wide ranges in the thermochemical properties of hydroxyl-terminated polybutadiene (HTPB), particularly the heat of formation. Six group additive schemes were used to estimate the heat of formation of HTPB and predict decreases due to increased hydroxyl functionality and curing reactions. Chemical equilibrium analyses showed that variations in the heat of formation of HTPB can impact combustion gas properties and theoretical propellant performance within practical operating conditions.
Article
Thermodynamics
James C. Thomas, Felix A. Rodriguez, Eric L. Petersen
Summary: This study evaluates the effects of various metal additives on the performance of hybrid rockets and finds that the inclusion of metal additives can reduce the regression rate without significantly affecting the combustion efficiency. Among the additives, zirconium is the best choice. Additionally, the combustion efficiency is well correlated with the combustion residence time.
COMBUSTION SCIENCE AND TECHNOLOGY
(2023)
Article
Energy & Fuels
Olivier Mathieu, Claire M. Gregoire, Mattias A. Turner, Darryl J. Mohr, Sulaiman A. Alturaifi, James C. Thomas, Eric L. Petersen
Summary: Through experiments and numerical analysis, it was found that modern detailed kinetics mechanisms can accurately predict the combustion properties of thermal runaway gases from a lithium-ion battery.
Article
Mechanics
J. C. Thomas, F. A. Rodriguez, D. S. Teitge, L. N. Kunka, G. N. Gaddis, Z. K. Browne, C. B. Ahumada, E. T. Balci, S. Jackson, E. L. Petersen, E. S. Oran
Summary: This paper describes an experimental evaluation of shock wave transmission from a detonating gas mixture in an open-ended tube into an inert atmosphere. The results show the successful deflagration-to-detonation transition and the formation of a transmitted shock wave. The study also characterizes the transmission of the shock wave into the surrounding environment and the conditions behind the transmitted shock wave.
Article
Energy & Fuels
Claire M. Gregoire, Charles K. Westbrook, Olivier Mathieu, Sean P. Cooper, Sulaiman A. Alturaifi, Eric L. Petersen
Summary: This study presents the kinetic treatment of the full group of C5 olefins and investigates the impact of C=C double bond position and branching on combustion properties through experimental measurements and numerical predictions. The results show noticeable differences between different isomers and provide insights into the combustion behavior of pentene isomers.
Article
Energy & Fuels
Claire M. Gregoire, Sean P. Cooper, Eric L. Petersen
Summary: Toluene oxidation was investigated using laser diagnostics to measure carbon monoxide and water profiles. The results are important for validating chemical kinetics mechanisms under highly dilute conditions.
Article
Chemistry, Physical
Claire M. Gregoire, Charles K. Westbrook, Sean P. Cooper, Mattias A. Turner, Sulaiman A. Alturaifi, Olivier Mathieu, Eric L. Petersen
Summary: The combustion properties of a gasoline-like blend of pentene isomers were investigated using various experimental measurements. Laminar flame speeds and ignition delay times were analyzed, along with CO time-history profiles. Numerical predictions using a validated chemical kinetics mechanism were presented, showing excellent results in modeling pentene-isomer combustion chemistry.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Physical
Damien Nativel, Can Shao, Sean P. Cooper, Eric L. Petersen, Christof Schulz, Mustapha Fikri, Sebastian Peukert
Summary: The influence of methanol and butanol on soot formation during the pyrolysis of a toluene primary reference fuel mixture was investigated. It was found that soot formed during the pyrolysis is primarily caused by the thermal decomposition of toluene. Adding methanol results in a slight reduction of soot formation, while adding butanol shifts the soot formation to higher temperatures without overall reduction.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Thermodynamics
Claire M. Gregoire, Eric L. Petersen, Olivier Mathieu
Summary: This study investigates the pyrolysis of ethylene carbonate and evaluates the performance of an existing chemical kinetics mechanism. A tentative model is proposed to improve predictions, highlighting the need for further research.
COMBUSTION AND FLAME
(2023)
Article
Energy & Fuels
Matthew G. Sandberg, Claire M. Gregoire, Darryl J. Mohr, Olivier Mathieu, Eric L. Petersen
Summary: This study investigates the effect of norbornadiene (NBD) as a fuel additive on ignition delay times of hydrogen and methane mixtures. The results show that NBD can significantly decrease the ignition delay time for methane, but dramatically increase it for hydrogen reactions.
Article
Engineering, Aerospace
Felix A. Rodriguez, James C. Thomas, Thomas E. Sammet, David S. Teitge, Eric L. Petersen
Summary: Ammonium perchlorate (AP) is a commonly used oxidizer in composite propellants, and its combustion behavior can be controlled by micro- and nano-metal oxide catalysts. The study found that micro-iron oxide increased the burning rate of AP within a certain pressure range, while nano-titanium oxide and nano-iron oxide increased the burning rate at higher pressures. The presence of catalytic additives eliminated the negative slope typically observed in the burning rate curve of plain AP, and nano-additive formulations showed higher low-pressure deflagration limits.
JOURNAL OF PROPULSION AND POWER
(2022)
Article
Thermodynamics
Mattias A. Turner, Pradeep Parajuli, Waruna D. Kulatilaka, Eric L. Petersen
Summary: In this study, chemiluminescence spectra of atmospheric-pressure flames doped with phosphorus-containing compounds were analyzed. The intensity of the doped flame emission increased relative to the neat flames, but no clear spectral features were identified. The observed continuum emission is attributed to blackbody emission from high-temperature soot particles.
JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER
(2022)
