Download or read book Simplified Kinetic Schemes for the Oxidation of Hydrocarbon Fuels Using a Numerical Laminar Flame Model written by Ioannis C. Diakos and published by . This book was released on 1990 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Simplified Reaction Mechanisms Using Continuous Thermodynamics for Hydrocarbon Fuels written by Clayton D.L. Fox and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Commercial fuels are mixtures with large numbers of components. Continuous thermodynamics is a technique for modelling fuel mixtures using a probability density function rather than dealing with each discreet component. The mean and standard deviation of the distribution are then used to model the chemical reactions of the mixture. This thesis develops the necessary theory to apply the technique of continuous thermodynamics to the oxidation reactions of hydrocarbon fuels. The theory is applied to three simplified models of hydrocarbon oxidation: a global one-step reaction, a two-step reaction with CO as the intermediate product, and the four-step reaction of Müller et al. (1992), which contains a high- and a low-temperature branch. These are all greatly simplified models of the complex reaction kinetics of hydrocarbons, and in this thesis they are applied specifically to n-paraffin hydrocarbons in the range from n-heptane to n-hexadecane. The model is tested numerically using a simple constant pressure homogeneous ignition problem using Cantera and compared to simplified and detailed mechanisms for n-heptane. The continuous thermodynamics models are able not only to predict ignition delay times and the development of temperature and species concentrations with time, but also changes in the mixture composition as reaction proceeds as represented by the mean and standard deviation of the distribution function. Continuous thermodynamics is therefore shown to be a useful tool for reactions of multicomponent mixtures, and an alternative to the "surrogate fuel" approach often used at present.
Download or read book Ignition Kinetics in Fuels Oxidation written by and published by . This book was released on 2006 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: This program studies fundamental chemical kinetics as well as its individual and coupled effects with aerodynamics on laminar nonpremixed ignition and flame propagation for hydrocarbons, through experimental, computational, and theoretical approaches. During the reporting period, three projects were undertaken, namely: (1) Experimental determination of high-pressure laminar flame speeds and kinetic modeling of carbon-monoxide I hydrogen combustion; (2) experimental and computational determination of the ignition temperatures and reaction mechanism of 1,3-butadiene at atmospheric and elevated pressures; and (3) experimental and computational studies on the ignition of the butene isomers.
Download or read book Oxygen Enhanced Combustion Second Edition written by Charles E. Baukal Jr. and published by CRC Press. This book was released on 2013-03-15 with total page 795 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion technology has traditionally been dominated by air/fuel combustion. However, two developments have increased the significance of oxygen-enhanced combustion—new technologies that produce oxygen less expensively and the increased importance of environmental regulations. Advantages of oxygen-enhanced combustion include less pollutant emissions as well as increased energy efficiency and productivity. Oxygen-Enhanced Combustion, Second Edition compiles information about using oxygen to enhance industrial heating and melting processes. It integrates fundamental principles, applications, and equipment design in one volume, making it a unique resource for specialists implementing the use of oxygen in combustion systems. This second edition of the bestselling book has more than doubled in size. Extensively updated and expanded, it covers significant advances in the technology that have occurred since the publication of the first edition. What’s New in This Edition Expanded from 11 chapters to 30, with most of the existing chapters revised A broader view of oxygen-enhanced combustion, with more than 50 contributors from over 20 organizations around the world More coverage of fundamentals, including fluid flow, heat transfer, noise, flame impingement, CFD modeling, soot formation, burner design, and burner testing New chapters on applications such as flameless combustion, steel reheating, iron production, cement production, power generation, fluidized bed combustion, chemicals and petrochemicals, and diesel engines This book offers a unified, up-to-date look at important commercialized uses of oxygen-enhanced combustion in a wide range of industries. It brings together the latest knowledge to assist those researching, engineering, and implementing combustion in power plants, engines, and other applications.
Download or read book The Gas Phase Oxidation of Hydrocarbons written by V. Ya. Shtern and published by Elsevier. This book was released on 2016-07-29 with total page 721 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gas-Phase Oxidation of Hydrocarbons reviews research on the mechanism of oxidation of paraffins, naphthenes, olefines, and aromatic hydrocarbons and explains in detail the phenomena and theories with significant kinetic equations and graphs. This book first presents a study of the development of research on the gaseous-phase oxidation of hydrocarbons. The non-chain schemes for the oxidation of hydrocarbons, such as hydroxylation, peroxidation, and aldehyde and dehydrogenation schemes, are then discussed. This book also presents experimental investigations and important topics such as oxidation of methane and olefinic hydrocarbons. This selection will be invaluable to students and experts in the field of chemistry and related disciplines.
Download or read book Turbulent Premixed Flames written by Nedunchezhian Swaminathan and published by Cambridge University Press. This book was released on 2011-04-25 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: A work on turbulent premixed combustion is important because of increased concern about the environmental impact of combustion and the search for new combustion concepts and technologies. An improved understanding of lean fuel turbulent premixed flames must play a central role in the fundamental science of these new concepts. Lean premixed flames have the potential to offer ultra-low emission levels, but they are notoriously susceptible to combustion oscillations. Thus, sophisticated control measures are inevitably required. The editors' intent is to set out the modeling aspects in the field of turbulent premixed combustion. Good progress has been made on this topic, and this cohesive volume contains contributions from international experts on various subtopics of the lean premixed flame problem.
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 Energy Research Abstracts written by and published by . This book was released on 1990 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis Gas Combustion written by Tim Lieuwen and published by CRC Press. This book was released on 2009-09-16 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coal, still used to generate more than half of the electric power in the U.S., will likely be part of any future global energy plan. But this finite resource is also responsible for 80 percent of the CO2 emissions from power production, and its continued use will require improved processing techniques that are less damaging to the environment and l
Download or read book Towards a Practical Modeling Approach for Low Temperature Oxidation of Fuels written by Rishav Choudhary and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The diversity of reactivities, intermediates, and pathways associated with the low-temperature oxidation of various component classes that constitute real fuels is perhaps the most challenging aspect of modeling combustion chemistry of these fuels. Unlike high-temperature oxidation (T > 1000 K), where the law of large numbers renders global combustion properties of real, multicomponent fuels weakly sensitive to compositional variability, reactions controlling low-temperature oxidation are very sensitive to fuel composition. Despite this fuel specificity, the formation of intermediates during low-temperature oxidation exhibits certain commonalities which can be observed in carefully designed shock tube experiments. Combining these observations with elemental balance, chemical kinetic considerations, and with the already mature Hybrid Chemistry (HyChem) approach for high-temperature oxidation of real fuels, I first propose an approach to develop simplified, physics-based chemical kinetic models for low-temperature oxidation of real fuels. In this approach, the low-temperature oxidation is described by lumped, fuel-specific reactions whose rate constants and stoichiometric parameters are determined using shock tube species time history measurements. These reactions augment the already developed high-temperature HyChem models which encompass fuel-specific reactions describing thermal and oxidative pyrolysis at high temperatures, and a detailed model describing kinetics of small hydrocarbons. Detailed arguments in support of the model formulation are presented. The model is then exercised to identify species to be targeted for measurements in shock tubes. Carbon monoxide (CO), and formaldehyde (CH2O) were identified as the most important species for determining the model parameters followed by OH, and HO2. Laser absorption spectroscopy based diagnostics for measuring some of these species were also developed in parallel with this work. The feasibility of the targeted speciation studies is first demonstrated during oxidation of five neat hydrocarbons, i.e., n-decane, n-octane, n-heptane, and its two branched isomers, 2-methyl hexane, and 3,3-dimethyl pentane. These studies not only demonstrated the feasibility of the diagnostics, but also highlighted the deficiency in the existing detailed models for low-temperature oxidation of heavy hydrocarbons. They also provided further evidence supporting some of the assumptions made while formulating the LT-HyChem approach. With the speciation strategy developed, and target experimental conditions verified, the application of the LT-HyChem approach to three classes of fuels is presented: a) A simple, three-component hydrocarbon mixture (TPRF-60), b) A jet fuel, c) Two high-performance gasoline fuels. Validation of the model against a range of ignition delay time (IDT) measurements conducted across a range of facilities worldwide is presented. The model predictions for all fuels show excellent agreement with the IDTs reported in the literature over a wide range of conditions. Moreover, the constraints imposed on the model parameters by the species time history measurements conducted in shock tubes result in a significant reduction in the uncertainty in the model's predictions. A detailed uncertainty analysis is presented and is supplemented with sensitivity analysis to identify the dominant contributing factors to the uncertainty in model predictions. The success of the LT-HyChem approach is encouraging as this approach can be extended to the sustainable fuels that will drive the engines of tomorrow. This will enable a rapid screening of candidates for the sustainable fuels of tomorrow.
Download or read book Detailed Chemical Kinetic Model for Oxygenated Fuels written by Sung-Woo Park and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed chemical kinetic model is developed and tested for the combustion of C2 and C3 oxygenated fuels such as ethanol, DME (dimethyl ether), acetone and n-propanol. It is validated by comparing predictions with experimental data on the structure of low pressure burner stabilised premixed flames and laminar burning velocities over a wide range of equivalence ratios. Data from shock tube and stirred reactor studies has also been considered. The elementary reactions of ethanol and DME oxidation have been studied extensively and were used as a starting point for extension to C3 oxygenated fuels. The chemistry of acetylene which is one of major intermediate species in higher hydrocarbon flames was also updated to improve the reliability of the present mechanism and acetylene laminar burning velocities and low-pressure premixed lean and rich flames were also computed. The detailed mechanism features more than 1500 reaction steps and 269 species. The structure of laminar premixed flames are predicted by using measured temperature profiles and conditions cover fuel-lean and fuel-rich mixtures at low pressure. The profiles of reactants, products and major intermediate species are compared to experimental data from mass spectrometry and the overall agreement between the kinetic model and experimental data is satisfactory. An analytic study of fuel consumption pathways is carried out to understand the detailed consumption pathways. The present mechanism is also tested against laminar flame speeds by calculating freely propagating premixed flames to extend the understanding of the combustion characteristics of oxygenated fuels. A sensitivity analysis is also performed.
Download or read book Reduced Kinetic Mechanisms and Asymptotic Approximations for Methane Air Flames written by Mitchell D. Smooke and published by Springer. This book was released on 2014-03-12 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this comprehensive text a systematic numerical and analytical treatment of the procedures for reducing complicated systems to a simplified reaction mechanism is presented. The results of applying the reduced reaction mechanism to a one-dimensional laminar flame are discussed. A set of premixed and non-premixed methane-air flames with simplified transport and skeletal chemistry are employed as test problems that are used later on to evaluate the results and assumptions in reduced reaction networks. The first four chapters form a short tutorial on the procedures used in formulating the test problems and in reducing reaction mechanisms by applying steady-state and partial-equilibrium approximations. The final six chapters discuss various aspects of the reduced chemistry problem for premixed and nonpremixed combustion.
Download or read book MILD Combustion Modelling Challenges Experimental Configurations and Diagnostic Tools written by Alessandro Parente and published by Frontiers Media SA. This book was released on 2021-11-26 with total page 160 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.
Download or read book Simplified Reaction Mechanisms for the Oxidation of Hydrocarbon Fuels in Flames written by C. K. Westbrook and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Analysis of Carbon Monoxide Flames by Reduced Kinetic and Asymptotic Methods written by Maria Lynn Jason Rightley and published by . This book was released on 1996 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent Combustion written by Norbert Peters and published by Cambridge University Press. This book was released on 2000-08-15 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: The combustion of fossil fuels remains a key technology for the foreseeable future. It is therefore important that we understand the mechanisms of combustion and, in particular, the role of turbulence within this process. Combustion always takes place within a turbulent flow field for two reasons: turbulence increases the mixing process and enhances combustion, but at the same time combustion releases heat which generates flow instability through buoyancy, thus enhancing the transition to turbulence. The four chapters of this book present a thorough introduction to the field of turbulent combustion. After an overview of modeling approaches, the three remaining chapters consider the three distinct cases of premixed, non-premixed, and partially premixed combustion, respectively. This book will be of value to researchers and students of engineering and applied mathematics by demonstrating the current theories of turbulent combustion within a unified presentation of the field.
