Download or read book Development and Optimization of a Comprehensive Kinetic Model of Hydrocarbon Fuel Combustion written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this research program was to develop a comprehensive, predictive, and detailed kinetic model of hydrocarbon combustion for aero propulsion simulations. Sensitivity analyses were performed to examine the influences of the uncertainty in binary diffusion coefficients on flame simulations. First-principles calculations were carried out to determine the molecular binary diffusion coefficients of H-He, H2-He, H-H2, and H-Ar gas mixtures. This study resulted in an updated transport property library commonly used in combustion simulations. A new class of radical-chain initiation reactions was discovered for the homogeneous oxidation of unsaturated hydrocarbons. This element of the study utilized advanced quantum chemistry tools, reaction rate theory, and the method of detailed kinetic modeling. This new class of initiation reactions was found to be critical to reaction model development. A detailed reaction model of C1-C4 fuel combustion was updated. The foundation of this model, namely the H2/CO sub-model, was revised completely and optimized. A new method, termed the Sensitivity Analysis Based (SAB) method, was developed for rapid model optimization. The method was shown to be far more efficient than the factorial design method used in previous kinetic model optimization efforts.
Download or read book Cleaner Combustion written by Frédérique Battin-Leclerc and published by Springer Science & Business Media. This book was released on 2013-09-06 with total page 657 pages. Available in PDF, EPUB and Kindle. Book excerpt: This overview compiles the on-going research in Europe to enlarge and deepen the understanding of the reaction mechanisms and pathways associated with the combustion of an increased range of fuels. Focus is given to the formation of a large number of hazardous minor pollutants and the inability of current combustion models to predict the formation of minor products such as alkenes, dienes, aromatics, aldehydes and soot nano-particles which have a deleterious impact on both the environment and on human health. Cleaner Combustion describes, at a fundamental level, the reactive chemistry of minor pollutants within extensively validated detailed mechanisms for traditional fuels, but also innovative surrogates, describing the complex chemistry of new environmentally important bio-fuels. Divided into five sections, a broad yet detailed coverage of related research is provided. Beginning with the development of detailed kinetic mechanisms, chapters go on to explore techniques to obtain reliable experimental data, soot and polycyclic aromatic hydrocarbons, mechanism reduction and uncertainty analysis, and elementary reactions. This comprehensive coverage of current research provides a solid foundation for researchers, managers, policy makers and industry operators working in or developing this innovative and globally relevant field.
Download or read book Development of a Comprehensive and Predictive Reaction Mechanism of Liquid Hydrocarbon Combustion written by and published by . This book was released on 2007 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies were conducted in several relevant areas, including (1) validation of the chemistry and transport models against the extinction of ultra-lean premixed hydrogen-air mixtures, (2) a comprehensive theoretical analysis of the reaction kinetics of carbon monoxide and the hydroxyl radical, (3) a theoretical kinetic study of the decomposition of ethylene oxide; (4) a gas-kinetic analysis for the transport properties of long chain molecules in dilute gases, (5) quantum-chemistry, master equation modeling of the unimolecular decomposition of ortho-benzyne, (6) extension of the previously developed hydrogenicarbon model to combustion pressures as high as 600 atm, (7) an updated kinetic mechanism of small-hydrocarbon fuel combustion for use as a kinetic foundation of higher hydrocarbon combustion, and (8) a methodology for kinetic uncertainty propagation. These projects represent the two key ingredients for meeting the overall project objectives: (a) an accurate physico-chemical property database for combustion kinetics, and (b) a unified and optimized kinetic model for liquid aliphatic and aromatic fuel combustion with quantifiable uncertainties.
Download or read book Army Research Office and Air Force Office of Scientific Research 2002 Contractors Meeting in Chemical Propulsion written by David M. Mann and published by . This book was released on 2002 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstracts are given for 6.1 basic research in chemical propulsion sponsored by the Army Research Office and the Air Force Office of Scientific Research.
Download or read book Development of a Generalised Kinetic Model for the Combustion of Hydrocarbon Fuels written by Matthew Ryan Fry and published by . This book was released on 2010 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 2019-06-06 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 A New Comprehensive Reaction Mechanism for Combustion of Hydrocarbon Fuels written by and published by . This book was released on 1993 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: A chemical kinetic model has been developed which describes pyrolysis, ignition and oxidation of many small hydrocarbon fuels over a wide range of experimental conditions. Fuels include carbon monoxide and hydrogen, methane and other alkane species up to n-butane, ethylene, propene, acetylene, and oxygenated species such as methanol, acetaldehyde and ethanol. Formation of some larger intermediate and product species including benzene, butadiene, large olefins, and cyclopentadiene has been treated in a semi-empirical manner. The reaction mechanism has been tested for conditions that do not involve transport and diffusional processes, including plug flow and stirred reactors, batch reactors and shock tubes. The present kinetic model and its validation differ from previous reaction mechanisms in two ways. First, in addition to conventional combustion data, experiments more commonly associated with chemical engineering problems such as oxidative coupling, oxidative pyrolysis and steam cracking are used to test the reaction mechanism, making it even more general than previous models. In addition, H atom abstraction and some other reaction rates, even for the smaller C2, C3 and C4 species, are treated using approximations that facilitate future extensions to larger fuels in a convenient manner. Construction of the reaction mechanism and comparisons with experimental data illustrate the generality of the model.
Download or read book Advances in Clean Hydrocarbon Fuel Processing written by M. Rashid Khan and published by Elsevier. This book was released on 2011-09-23 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conventional coal, oil and gas resources used worldwide for power production and transportation are limited and unsustainable. Research and development into clean, alternative hydrocarbon fuels is therefore aimed at improving fuel security through exploring new feedstock conversion techniques, improving production efficiency and reducing environmental impacts. Advances in clean hydrocarbon fuel processing provides a comprehensive and systematic reference on the range of alternative conversion processes and technologies. Following introductory overviews of the feedstocks, environmental issues and life cycle assessment for alternative hydrocarbon fuel processing, sections go on to review solid, liquid and gaseous fuel conversion. Solid fuel coverage includes reviews of liquefaction, gasification, pyrolysis and biomass catalysis. Liquid fuel coverage includes reviews of sulfur removal, partial oxidation and hydroconversion. Gaseous fuel coverage includes reviews of Fischer-Tropsch synthesis, methanol and dimethyl ether production, water-gas shift technology and natural gas hydrate conversion. The final section examines environmental degradation issues in fuel processing plants as well as automation, advanced process control and process modelling techniques for plant optimisation Written by an international team of expert contributors, Advances in clean hydrocarbon fuel processing provides a valuable reference for fuel processing engineers, industrial petrochemists and energy professionals, as well as for researchers and academics in this field. A comprehensive reference on the range of alternative conversion processes and technologies Provides an overview of the feedstocks, environmental issues and life cycle assessments for alternative hydrocarbon fuel processing, including a review of the key issues in solid, liquid and gaseous fuel conversion Examines automation, advanced process control and process modelling techniques for plant optimisation
Download or read book Hydrocarbon Combustion Reaction Models from Both Ends the Foundational Fuels and JP10 written by Yujie Tao and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to the hierarchical nature of high-temperature hydrocarbon oxidation, modeling the combustion chemistry of higher hydrocarbon fuels typically requires a fuel-specific reaction model that describes the fragmentation of the fuel to small species, and a foundational fuel chemistry model that describes the oxidation of these species. Shared by the combustion of large hydrocarbons, the foundational fuel chemistry is also the rate-limiting step and therefore a crucial part for constructing reliable combustion models for any higher hydrocarbons. The dissertation studies the aforementioned problems from both ends. A detailed reaction kinetic model of the foundational fuel combustion is comprised of elementary chemical reactions and their associated rate coefficients. Each of the rate coefficients comes with some uncertainty. The inherent uncertainties of the rate parameters propagate into model predictions and need to be properly quantified. Without characterizing the uncertainty, a reaction model merely represents a feasible combination of rate parameters within a high-dimensional uncertainty space. The Foundational Fuel Chemistry Model (FFCM) is an effort directed at developing a reliable combustion model for the foundational fuels with rate parameters optimized and uncertainty minimized. The first version, FFCM-1, optimized for H2, H2/CO, CH2O and CH4 combustion was constrained with carefully evaluated fundamental combustion data that includes laminar flame speeds, shock tube ignition delay times, shock tube species profiles, and flow reactor species profiles. It has been shown that the model reconciles all the experimental targets chosen and has significantly reduced prediction uncertainties. The remaining kinetic uncertainties in FFCM-1 were further analyzed with extinction and ignition residence time predictions in perfectly-stirred reactor conditions. The reactions that were responsible for the remaining prediction uncertainties were studied with an impact factor analysis over a wide range of temperature, pressure and equivalence ratio. The optimization and uncertainty quantification procedure was then extended to also include temperature dependency by considering the joint optimization of pre-exponential factors and activation energies. An effective temperature was defined for every target and utilized in the response surface derivation. The resulting temperature-dependent uncertainties of key reactions in H2/CO flames in a test problem were discussed. JP10 was studied as a single-component large-fuel example, using the Hybrid Chemistry (HyChem) approach. The HyChem approach assumes a decoupled fuel pyrolysis and oxidation of pyrolysis products. The pyrolysis model is described with highly-lumped steps and optimized against experimental data from shock tube and flow reactor species profiles and shock tube ignition delay. Special attention was paid to the unique molecular structure of the fuel in the lumped pyrolysis reactions, and the overall performance of the model is shown to be satisfactory.
Download or read book The Role of Comprehensive Detailed Chemical Kinetic Reaction Mechanisms in Combustion Research written by and published by . This book was released on 2008 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent developments by the authors in the field of comprehensive detailed chemical kinetic reaction mechanisms for hydrocarbon fuels are reviewed. Examples are given of how these mechanisms provide fundamental chemical insights into a range of combustion applications. Practical combustion consists primarily of chemical heat release from reactions between a fuel and an oxidizer, and computer simulations of practical combustion systems have become an essential tool of combustion research (Westbrook et al., 2005). At the heart of most combustion simulations, the chemical kinetic submodel frequently is the most detailed, complex and computationally costly part of a system model. Historically, the chemical submodel equations are solved using time-implicit numerical algorithms, due to the extreme stiffness of the coupled rate equations, with a computational cost that varies roughly with the cube of the number of chemical species in the model. While early mechanisms (c. 1980) for apparently simple fuels such as methane (Warnatz, 1980) or methanol (Westbrook and Dryer, 1979) included perhaps 25 species, current detailed mechanisms for much larger, more complex fuels such as hexadecane (Fournet et al., 2001; Ristori et al., 2001; Westbrook et al., 2008) or methyl ester methyl decanoate (Herbinet et al., 2008) have as many as 2000 or even 3000 species. Rapid growth in capabilities of modern computers has been an essential feature in this rapid growth in the size and complexity of chemical kinetic reaction mechanisms.
Download or read book Development of Detailed Kinetic Models for Fischer Tropsch Fuels written by and published by . This book was released on 2008 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fischer-Tropsch (FT) fuels can be synthesized from a syngas stream generated by the gasification of biomass. As such they have the potential to be a renewable hydrocarbon fuel with many desirable properties. However, both the chemical and physical properties are somewhat different from the petroleum-based hydrocarbons that they might replace, and it is important to account for such differences when considering using them as replacements for conventional fuels in devices such as diesel engines and gas turbines. FT fuels generally contain iso-alkanes with one or two substituted methyl groups to meet the pour-point specifications. Although models have been developed for smaller branched alkanes such as isooctane, additional efforts are required to properly capture the kinetics of the larger branched alkanes. Recently, Westbrook et al. developed a chemical kinetic model that can be used to represent the entire series of n-alkanes from C1 to C16 (Figure 1). In the current work, the model is extended to treat 2,2,4,4,6,8,8-heptamethylnonane (HMN), a large iso-alkane. The same reaction rate rules used in the iso-octane mechanism were incorporated in the HMN mechanism. Both high and low temperature chemistry was included so that the chemical kinetic model would be applicable to advanced internal combustion engines using low temperature combustion strategies. The chemical kinetic model consists of 1114 species and 4468 reactions. Concurrently with this effort, work is underway to improve the details of specific reaction classes in the mechanism, guided by high-level electronic structure calculations. Attention is focused upon development of accurate rate rules for abstraction of the tertiary hydrogens present in branched alkanes and properly accounting for the pressure dependence of the?-scission, isomerization, and R + O2 reactions.
Download or read book 40th AIAA Aerospace Sciences Meeting Exhibit written by and published by . This book was released on 2002 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Key Factors of Combustion written by Nikolai M. Rubtsov and published by Springer. This book was released on 2016-11-13 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the main advances in the mechanisms of combustion processes. It focuses on the analysis of kinetic mechanisms of gas combustion processes and experimental investigation into the interrelation of kinetics and gas dynamics in gas combustion. The book is complimentary to the one previously published, The Modes of Gaseous Combustion.
Download or read book Combustion Chemistry and the Carbon Neutral Future written by Kenneth Brezinsky and published by Elsevier. This book was released on 2023-02-16 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the demands for cleaner, more efficient, reduced and zero carbon emitting transportation increase, the traditional focus of Combustion Chemistry research is stretching and adapting to help provide solutions to these contemporary issues. Combustion Chemistry and the Carbon Neutral Future: What will the Next 25 Years of Research Require? presents a guide to current research in the field and an exploration of possible future steps as we move towards cleaner, greener and reduced carbon combustion chemistry. Beginning with a discussion of engine emissions and soot, the book goes on to discuss a range of alternative fuels, including hydrogen, ammonia, small alcohols and other bio-oxygenates, natural gas, syngas and synthesized hydrocarbon fuels. Methods for predicting and improving efficiency and sustainability, such as low temperature and catalytic combustion, chemical looping, supercritical fluid combustion, and diagnostic monitoring even at high pressure, are then explored. Some novel aspects of biomass derived aviation fuels and combustion synthesis are also covered. Combining the knowledge and experience of an interdisciplinary team of experts in the field, Combustion Chemistry and the Carbon Neutral Future: What will the Next 25 Years of Research Require? is an insightful guide to current and future focus areas for combustion chemistry researchers in line with the transition to greener, cleaner technologies. Provides insight on current developments in combustion chemistry as a tool for supporting a reduced-carbon future Reviews modeling and diagnostic tools, in addition to key approaches and alternative fuels Includes projections for the future from leaders in the field, pointing current and prospective researchers to potentially fruitful areas for exploration
Download or read book Dynamic Simulation Optimization and Control of Flexible Chemical looping Combustion Processes written by Lu Han and published by . This book was released on 2016 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamental and Semi global Kinetic Mechanisms of Hydrocarbon Combustion Annual Report October 1 1977 September 30 1978 written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Aimed at understanding practical combustion environments, present modeling efforts have been hampered by difficulties related to coupling combustion chemistry to the complex fluid mechanics present. In an attempt to circumvent such difficulties the present research program is aimed at the development of simplified chemical kinetic models (usually termed global models) to represent the combustion chemistry. Initially aimed at simple hydrocarbon fuels the program is progressing to studies of more complex aliphatics as well as important alternative fuels. The objective of this research is multifold: (a) to determine mechanistic oxidation routes of hydrocarbons derived from crudes and alternate sources, so that efficient and environmentally clean power plants based on internal and external combustion processes can be designed; (b) to develop and validate actual simplified (global) reaction rates for these hydrocarbons so that these power plants can be modelled; and (c) to develop an understanding of particulate (soot) formation to permit the rapid and successful introduction of the inexpensive, heavy, highly aromatic fuels. Studies of paraffin, olefin and alcohol hydrocarbons are reviewed. Appropriate global models are presented and compared with experimental data. The results clearly demonstrate that the turbulent flow reactor facility can be used to develop accurate global models for a variety of important fuels.
