Download or read book Determining Detailed Reaction Kinetics for Nitrogen and Oxygen Containing Fuels written by Nicole Jeanne Labbe and published by . This book was released on 2013 with total page 813 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the emergence of new biorenewable transportation fuels, the role of heteroatoms in combustion has increased tremendously. While petroleum-based fuels are primarily hydrocarbons, many biorenewable fuels contain heteroatoms such as oxygen and nitrogen, introducing new challenges associated with toxic emissions. A fundamental understanding of the chemical kinetics of combustion of these heteroatomic fuels is necessary to elucidate the pathways by which these toxic emissions are formed and may be achieved through the development of combustion models. Reaction sets, the core of these combustion models, may be assembled for individual fuels through a balance of employing vetted rate constants from prior publications, quantum chemistry calculations, and rate constant estimations. For accuracy, reaction sets should be tested against experimental combustion studies such as low-pressure flame experiments using molecular-beam mass spectrometry (MBMS) or chemiluminescence and high-pressure shock-tube experiments. This dissertation presents the development of a new reaction set to describe gas-phase combustion chemistry of fuels containing only hydrogen, carbon, oxygen, and nitrogen. The foundation of this model was a reaction set to describe combustion of ammonia flames. This reaction set contains only H/N/O chemistry for simplicity. The new reaction set was tested against a pyrolysis shock-tube study, as well as 12 MBMS flame experiments under a variety of conditions, including different mixtures of fuels and oxidizers (NH3, N2O, H2, NO, O2), fuel equivalence ratios (lean to rich), pressures, and concentrations of diluent gas. Additionally, the base H/N/O mechanism was expanded to include carbon chemistry and was tested against flames of dimethylamine, ethylamine, and a methane/ammonia mixture. This reaction set was employed to study heterocyclic biofuels including a fuel-rich flame of tetrahydropyran, the monoether analogue to cyclohexane and the basic ring in cellulose. Additionally, the model was used in a study of morpholine, a 6-membered ring with both ether and amine functionalities, testing the model against fuel-rich flame studies using both MBMS and chemiluminescence techniques and high-pressure shock-tube studies for both oxidation and pyrolysis at elevated temperatures and pressures. Lastly, the model was used to study the combustion of hypergolic rocket fuels, specifically monomethyl hydrazine and tetramethylethyldiamine with red fuming nitric acid.
Download or read book Shock Tube Study of Nitrogen containing Fuels written by Sijie Li and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The combustion chemistry of nitrogen-containing fuels is important in the study of bio-derived fuels and nitrogen-based propellants. However, little high-quality shock tube kinetics data exists for these systems. The primary objective of the research presented in this dissertation is to augment the experimental database and to improve understanding of the chemical kinetics for four nitrogen-containing fuels: morpholine, dimethylamine, ethylamine and monomethylhydrazine. Morpholine (C4H9NO, 1-oxa-4-aza-cyclohexane) is a good representative candidate of a nitrogen-containing fuel because of its cyclic structure and wide industrial applications. Morpholine ignition delay times were measured behind reflected shock waves. A morpholine mechanism was developed based on this shock tube study and previous works in the literature. The simulations from this morpholine mechanism were in good agreement with the current morpholine experiments as well as previous morpholine flame data. Refinement of this morpholine mechanism required improvements in the sub-mechanisms of two major intermediate species dimethylamine and ethylamine, as discussed in a progressive manner in this dissertation. The overall rate constants of hydroxyl radicals (OH) with dimethylamine (DMA: CH3NHCH3) and ethylamine (EA: CH3CH2NH2) were measured behind reflected shock waves using UV laser absorption of OH radicals near 306.7 nm. The overall rate constants were determined by fitting the measured OH time-histories with the computed profiles using the detailed dimethylamine and ethylamine sub-mechanisms contained in the morpholine mechanism. Variational transition state theory was used to compute the H-abstraction rates by OH for dimethylamine and ethylamine. The calculated reaction rate constants are in good agreement with the experiment. The calculated reaction rate constants were used to update the morpholine mechanism for simulations in the following sections. Dimethylamine (DMA) ignition delay times and OH time-histories were investigated behind reflected shock waves. The dimethylamine ignition delay time measurements were carried out in 4% oxygen/argon. OH time-histories were measured in stoichiometric mixtures of 500 ppm DMA/O2/argon. The morpholine mechanism was then updated by adding the DMA unimolecular decomposition channel: DMA = CH3NH + CH3. With this modification, the simulation results are in excellent agreement with both the dimethylamine ignition delay times and OH time-history data. Ethylamine (CH3CH2NH2) pyrolysis and oxidation were studied behind reflected shock waves. For ethylamine pyrolysis, NH2 time-histories were measured in 2000 ppm ethylamine/argon mixtures. For ethylamine oxidation, ignition delay times, NH2 and OH time-histories were measured in ethylamine/O2/argon mixtures. By fitting the simulations to the early time-histories of NH2 and OH, the rate constants for the two major ethylamine decomposition pathways in the morpholine mechanism were updated for better agreement with the experiment. In addition, recommendations from recent theoretical studies of ethylamine radical reactions were implemented. With these modifications, the final updated morpholine mechanism provides significantly improved agreement with the species time-history measurements and the ignition delay times of ethylamine. The morpholine mechanism, after implementing the aformentioned updates based on the dimethylamine and ethylamine data, was compared with the morpholine ignition delay time data again. It was shown that those modifications improve the agreements of the mechanism with the morpholine data. Amine groups are common structural features for rocket propellants as well, and using the same approach as above, the pyrolysis of an important propellant monomethylhydrazine (MMH) was studied using NH2 time-histories in MMH/argon mixtures. The MMH pyrolysis mechanism developed by Sun et al. (2009), with the updates by Cook et al. (2011), was used to compare with the experiment. The rate constant of the reaction: MMH = CH3N.H + NH2 was determined based on early time of the NH2 time-histories. Pressure dependence of this reaction was observed at 0.3-5 atm. The measured reaction rate constants follow a pressure dependence trend close to the theoretical results by Zhang et al. (2011) based on transition state theory master equation analysis. Using the high and low-pressure limit expressions by Zhang et al., a new Troe's expression in the fall-off region was proposed based on the current experimental data. Utilizing the later times of the NH2 time-histories, a new reaction rate expression was recommended for the reaction: NHNH2 + H = NH2 + NH2.
Download or read book A Supplementary Bibliography of Kinetic Data on Gas Phase Reactions of Nitrogen Oxygen and Nitrogen Oxides written by Francis Westley and published by . This book was released on 1973 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supplementary Bibliography of Kinetic Data on Gas Phase Reactions of Nitrogen Oxygen and Nitrogen Oxides 1972 1973 written by Francis Westley and published by . This book was released on 1975 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gas Phase Combustion Chemistry written by W.C., Jr. Gardiner and published by Springer Science & Business Media. This book was released on 1999-12-10 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superseding Gardiner's "Combustion Chemistry", this is an updated, comprehensive coverage of those aspects of combustion chemistry relevant to gas-phase combustion of hydrocarbons. The book includes an extended discussion of air pollutant chemistry and aspects of combustion, and reviews elementary reactions of nitrogen, sulfur and chlorine compounds that are relevant to combustion. Methods of combustion modeling and rate coefficient estimation are presented, as well as access to databases for combustion thermochemistry and modeling.
Download or read book Mathematical Modelling of Gas Phase Complex Reaction Systems Pyrolysis and Combustion written by and published by Elsevier. This book was released on 2019-06-21 with total page 1034 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mathematical Modelling of Gas-Phase Complex Reaction Systems: Pyrolysis and Combustion, Volume 45, gives an overview of the different steps involved in the development and application of detailed kinetic mechanisms, mainly relating to pyrolysis and combustion processes. The book is divided into two parts that cover the chemistry and kinetic models and then the numerical and statistical methods. It offers a comprehensive coverage of the theory and tools needed, along with the steps necessary for practical and industrial applications. Details thermochemical properties and "ab initio" calculations of elementary reaction rates Details kinetic mechanisms of pyrolysis and combustion processes Explains experimental data for improving reaction models and for kinetic mechanisms assessment Describes surrogate fuels and molecular reconstruction of hydrocarbon liquid mixtures Describes pollutant formation in combustion systems Solves and validates the kinetic mechanisms using numerical and statistical methods Outlines optimal design of industrial burners and optimization and dynamic control of pyrolysis furnaces Outlines large eddy simulation of turbulent reacting flows
Download or read book Evaluated Kinetic Data for High Temperature Reactions Homogeneous gas phase reactions of the H2 N2 O2 system written by D. L. Baulch and published by . This book was released on 1972 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Kinetics and Dynamics of Elementary Gas Reactions written by Ian W. M. Smith and published by Butterworth-Heinemann. This book was released on 2013-10-22 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Kinetics and Dynamics of Elementary Gas Reactions surveys the state of modern knowledge on elementary gas reactions to understand natural phenomena in terms of molecular behavior. Part 1 of this book describes the theoretical and conceptual background of elementary gas-phase reactions, emphasizing the assumptions and limitations of each theoretical approach, as well as its strengths. In Part 2, selected experimental results are considered to demonstrate the scope of present day techniques and illustrate the application of the theoretical ideas introduced in Part 1. This publication is intended primarily for working kineticists and chemists, but is also beneficial to graduate students.
Download or read book The Oxidation of Hydrocarbons in the Liquid Phase written by N. M. Emanuel' and published by Elsevier. This book was released on 2013-11-19 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approx.424 pages
Download or read book Acid Precipitation written by and published by . This book was released on 1986 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1980 with total page 758 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Fossil Energy Update written by and published by . This book was released on 1977 with total page 1052 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration and published by . This book was released on 1976 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications and Abstracts of Theses written by University of Leeds and published by . This book was released on 1964 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Supplementary Bibliography of Kinetic Data on Gas Phase Reactions of Nitrogen Oxygen and Nitrogen Oxides written by Francis Westley and published by . This book was released on 1973 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt:
