Download or read book Chemical Kinetic Modeling of Combustion of Practical Hydrocarbon Fuels written by Charles K. Westbrook and published by . This book was released on 1989 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Kinetic Modeling of Combustion of Automotive Fuels written by W. J. Pitz and published by . This book was released on 2006 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this report are to: (1) Develop detailed chemical kinetic reaction models for components of fuels, including olefins and cycloalkanes used in diesel, spark-ignition and HCCI engines; (2) Develop surrogate mixtures of hydrocarbon components to represent real fuels and lead to efficient reduced combustion models; and (3) Characterize the role of fuel composition on production of emissions from practical automotive engines.
Download or read book Summary Report on the Workshop on High Temperature Chemical Kinetics Applications to Combustion Research written by National Measurement Laboratory (U.S.) and published by . This book was released on 1978 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Kinetics of the Gas Phase Combustion of Fuels written by Francis Westley and published by . This book was released on 1976 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Work supported by the Office of Standard Reference Data, National Bureau of Standards, Naval Sea Systems Command, Department of the Navy, and Division of Conservation, Research and Technology, Energy Research and Development Administration.
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 Fundamentals and Technology of Combustion written by F El-Mahallawy and published by Elsevier. This book was released on 2002-07-10 with total page 863 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals and Technology of Combustion contains brief descriptions of combustion fundamental processes, followed by an extensive survey of the combustion research technology. It also includes mathematical combustion modeling of the processes covering mainly premixed and diffusion flames, where many chemical and physical processes compete in complex ways, for both laminar and turbulent flows. The combustion chemistry models that validate experimental data for different fuels are sufficiently accurate to allow confident predictions of the flame characteristics. This illustrates a unique bridge between combustion fundamentals and combustion technology, which provides a valuable technical reference for many engineers and scientists. Moreover, the book gives the reader sufficient background of basic engineering sciences such as chemistry, thermodynamics, heat transfer and fluid mechanics. The combustion research and mathematical models fit between small-scale laboratory burner flames, and large-scale industrial boilers, furnaces and combustion chambers. The materials have been collected from previous relevant research and some selected papers of the authors and co-workers, which have been presented mainly in different refereed journals, international conferences and symposia, thus providing a comprehensive collection. Furthermore, the book includes some of the many recent general correlations for the characteristics of laminar, turbulent, premixed and diffusion flames in an easily usable form. The authors believe that further progress in optimizing combustion performance and reducing polluting emissions can only be treated through understanding of combustion chemistry.
Download or read book Chemical Kinetics of Hydrocarbon Ignition in Practical Combustion Systems written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical kinetic factors of hydrocarbon oxidation are examined in a variety of ignition problems. Ignition is related to the presence of a dominant chain branching reaction mechanism that can drive a chemical system to completion in a very short period of time. Ignition in laboratory environments is studied for problems including shock tubes and rapid compression machines. Modeling of the laboratory systems are used to develop kinetic models that can be used to analyze ignition in practical systems. Two major chain branching regimes are identified, one consisting of high temperature ignition with a chain branching reaction mechanism based on the reaction between atomic hydrogen with molecular oxygen, and the second based on an intermediate temperature thermal decomposition of hydrogen peroxide. Kinetic models are then used to describe ignition in practical combustion environments, including detonations and pulse combustors for high temperature ignition, and engine knock and diesel ignition for intermediate temperature ignition. The final example of ignition in a practical environment is homogeneous charge, compression ignition (HCCI) which is shown to be a problem dominated by the kinetics intermediate temperature hydrocarbon ignition. Model results show why high hydrocarbon and CO emissions are inevitable in HCCI combustion. The conclusion of this study is that the kinetics of hydrocarbon ignition are actually quite simple, since only one or two elementary reactions are dominant. However, there are many combustion factors that can influence these two major reactions, and these are the features that vary from one practical system to another.
Download or read book Combustion Chemistry written by W. C. Jr. Gardiner and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detailed study of the rates and mechanisms of combustion reactions has not been in the mainstream of combustion research until the recent recognition that further progress in optimizing burner performance and reducing pollutant emission can only be done with fundamental understanding of combustion chemistry. This has become apparent at a time when our understanding of the chemistry, at least of small-molecule combustion, and our ability to model combustion processes on large computers have developed to the point that real confidence can be placed in the results. This book is an introduction for outsiders or beginners as well as a reference work for people already active in the field. Because the spectrum of combustion scientists ranges from chemists with little computing experience to engineers who have had only one college chemistry course, everything needed to bring all kinds of beginners up to the level of current practice in detailed combustion modeling is included. It was a temptation to include critical discussions of modeling results and computer programs that would enable outsiders to start quickly into problem solving. We elected not to do either, because we feel that the former are better put into the primary research literature and that people who are going to do combustion modeling should either write their own programs or collaborate with experts. The only exception to this is in the thermochemical area, where programs have been included to do routine fitting operations. For reference purposes there are tables of thermochemical, transport-property, and rate coefficient data.
Download or read book Proceedings of the DOE NREL Hydrogen Program Review written by and published by . This book was released on 1994 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigations into the Combustion Kinetics of Several Novel Oxygenated Fuels written by Wenyu Sun and published by Springer Nature. This book was released on 2023-09-22 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, attention was paid to several novel oxygenated fuels—carbonates, polyethers and ketones. Combustion kinetic investigations were performed for typical representative compounds, including dimethyl carbonate, diethyl carbonate, cyclopentanone, 3-pentanone, 1,2-dimethoxyethane and dimethoxymethane. For experiments, suitable diagnostic techniques were used to measure the detailed speciation information of the target fuels under different conditions. For kinetic modeling, rate coefficients for crucial elementary reactions were obtained through high-level theoretical calculations. Based on that, validated kinetic models with good predictive performances were developed. On the basis of experimental measurements and model interpretations, this work highlighted two important combustion characteristics regarding the practical use: the pollutant formation and the ignition performance. Besides, the correlation between oxygen-containing functional groups and the aforementioned combustion characteristics was revealed. To reveal the potential interactions between the reaction networks of oxygenated additives and the hydrocarbon base fuels during combustion. Chemical structures of laminar premixed flames fueled by binary fuels were measured, and by changing the initial fuel compositions, the addition effects of the oxygenates on the fuel consumption and pollutant formation behaviors were explored. It was found that complicated chemical interactions do not exist in the reaction networks under the investigated conditions.
Download or read book Advanced Combustion Science written by Tsuneo Someya and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-uniform combustion, as encountered in diesel and gas turbine engines, furnaces, and boilers, is responsible for the conversion of fossil fuel to energy and also for the corresponding formation of pollutants. In spite of great research efforts in the past, the mechanism of non-uniform combustion has remained less explored than that of other combustion types, since it consists of many, mostly transient processes which influence each other. In view of this background, a group research project, "Exploration of Combustion Mechanism", was established to explore the mechanism of combustion, especially that of diffusive combustion, and also to find efficient ways to control the combustion process for better utilization of fuel and the reduction of pollutant emission. The group research was started, after preparatory activity of 2 years, in April 1988, for a period of 3 years, as a project with a Grant-in-Aid for Scientific Research of Priority Area subsidized by the Ministry of Education, Science and Culture of Japan. The entire group of 43 members was set up as an organizing committee of 13 members, and five research groups, consisting of 36 members. The research groups were: (1) Steady combustion, (2) Unsteady spray combustion, (3) Control of combustion, (4) Chemistry of combustion, and (5) Effects of fuels. At the beginning of the project it was agreed that we should pursue the mechanism of combustion from a scientific viewpoint, namely, the target of the project was to obtain the fundamentals, or "know why", rather than "know how" of combustion.
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 Evaluated Kinetic Data for High Temperature Reactions written by and published by . This book was released on 1972 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Kinetic Modeling of Component Mixtures Relevant to Gasoline written by and published by . This book was released on 2008 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detailed kinetic models of pyrolysis and combustion of hydrocarbon fuels are nowadays widely used in the design of internal combustion engines and these models are effectively applied to help meet the increasingly stringent environmental and energetic standards. In previous studies by the combustion community, such models not only contributed to the understanding of pure component combustion, but also provided a deeper insight into the combustion behavior of complex mixtures. One of the major challenges in this field is now the definition and the development of appropriate surrogate models able to mimic the actual features of real fuels. Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. Their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. Aside the most commonly used surrogates containing iso-octane and n-heptane only, the so called Primary Reference Fuels (PRF), new mixtures have recently been suggested to extend the reference components in surrogate mixtures to also include alkenes and aromatics. It is generally agreed that, including representative species for all the main classes of hydrocarbons which can be found in real fuels, it is possible to reproduce very effectively in a wide range of operating conditions not just the auto-ignition propensity of gasoline or Diesel fuels, but also their physical properties and their combustion residuals [1]. In this work, the combustion behavior of several components relevant to gasoline surrogate formulation is computationally examined. The attention is focused on the autoignition of iso-octane, hexene and their mixtures. Some important issues relevant to the experimental and modeling investigation of such fuels are discussed with the help of rapid compression machine data and calculations. Following the model validation, the behavior of mixtures is discussed on the basis of computational results.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992 with total page 824 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Chemical Kinetic Modeling of the Oxidation of C8 and Larger N alkanes and 2 methylalkanes written by and published by . This book was released on 2011 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conventional petroleum jet and diesel fuels, as well as alternative Fischer-Tropsch (FT) fuels and hydrotreated renewable jet (HRJ) fuels, contain high molecular weight lightly branched alkanes (i.e., methylalkanes) and straight chain alkanes (n-alkanes). Improving the combustion of these fuels in practical applications requires a fundamental understanding of large hydrocarbon combustion chemistry. This research project presents a detailed and reduced chemical kinetic mechanism for singly methylated iso-alkanes (i.e., 2-methylalkanes) ranging from C to C20. The mechanism also includes an updated version of our previously published C8 to C16 n-alkanes model. The complete detailed mechanism contains approximately 7,200 species 31,400 reactions. The proposed model is validated against new experimental data from a variety of fundamental combustion devices including premixed and nonpremixed flames, perfectly stirred reactors and shock tubes. This new model is used to show how the presence of a methyl branch affects important combustion properties such as laminar flame propagation, ignition, and species formation.
Download or read book Gaseous Detonations written by M.A. Nettleton and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: My introduction to the fascinating phenomena associated with detonation waves came through appointments as an external fellow at the Department of Physics, University College of Wales, and at the Department of Mechanical Engineering, University of Leeds. Very special thanks for his accurate guidance through the large body of information on gaseous detonations are due to Professor D. H. Edwards of University College of Wales. Indeed, the onerous task of concisely enumerating the key features of unidimensional theories of detonations was undertaken by him, and Chapter 2 is based on his initial draft. When the text strays to the use of we, it is a deserved acknow ledgement of his contribution. Again, I should like to thank Professor D. Bradley of Leeds University for his enthusiastic encouragement of my efforts at developing a model of the composition limits of detonability through a relationship between run-up distance and composition of the mixture. The text has been prepared in the context of these fellowships, and I am grateful to the Central Electricity Generating Board for its permission to accept these appointments.
