Download or read book Experimental and Kinetic Modeling Study of the Auto ignition Characteristics of the Four Isomers of Butanol written by Jeffrey T. Moss and published by . This book was released on 2008 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low and High Temperature Combustion Chemistry of Butanol Isomers in Premixed Flames and Autoignition Systems written by and published by . This book was released on 2010 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Butanol is a fuel that has been proposed as a bio-derived alternative to conventional petroleum derived fuels. The structural isomer in traditional 'bio-butanol' fuel is n-butanol, but newer conversion technologies produce iso-butanol as a fuel. In order to better understand the combustion chemistry of bio-butanol, this study presents a comprehensive chemical kinetic model for all the four isomers of butanol (e.g., 1-, 2-, iso- and tert-butanol). The proposed model includes detailed high temperature and low temperature reaction pathways. In this study, the primary experimental validation target for the model is premixed flat low-pressure flame species profiles obtained using molecular beam mass spectrometry (MBMS). The model is also validated against previously published data for premixed flame velocity and n-butanol rapid compression machine and shock tube ignition delay. The agreement with these data sets is reasonably good. The dominant reaction pathways at the various pressures and temperatures studied are elucidated. At low temperature conditions, we found that the reaction of alphahydroxybutyl with O2 was important in controlling the reactivity of the system, and for correctly predicting C4 aldehyde profiles in low pressure premixed flames. Enol-keto isomerization reactions assisted by HO2 were also found to be important in converting enols to aldehydes and ketones in the low pressure premixed flames. In the paper, we describe how the structural features of the four different butanol isomers lead to differences in the combustion properties of each isomer.
Download or read book Ignition of Isomers of Pentane written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrocarbon ignition is an important element in many practical combustion systems, including internal combustion engines, detonations, pulse combustors, and flame initiation. The rapid compression machine (RCM) is used frequently to study the kinetics of hydrocarbon autoignition [e.g., 1-7], since the reactive gas temperatures and time histories are similar to those seen in automotive engines during Diesel ignition and end gas autoignition leading to engine knock in spark-ignition engines. The RCM provides a rich environment for study of the theory of hydrocarbon oxidation, including degenerate chain branching, alkylperoxy radical isomerization and effects of thermal feedback [8]. The literature of hydrocarbon oxidation studies in the RCM has been summarized recently [9,10], and many classes of fuels have been studied. Detailed kinetic modeling is another tool available to study hydrocarbon oxidation in the RCM [4,11]. The aim of the present work is to determine experimentally the influence of variations in fuel molecular structure on autoignition, and to use a kinetic model to understand the reasons for those variations. This study is unique in that while other studies have addressed variations in pressure and equivalence ratio on ignition [11], this work addresses effects of variations in fuel molecular structure for all of the isomers of a single fuel formula, pentane, in a RCM. The three isomers of pentane possess many of the structural elements that determine such autoignition characteristics as octane number and variability in cool flame production, so this study will benefit our efforts to describe these effects.
Download or read book Autoignition Chemistry in a Motored Engine written by and published by . This book was released on 1996 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Autoignition of isomers of pentane, hexane, and primary reference fuel mixture of n-heptane and iso-octane has been studied experimentally under motored engine conditions and computationally using a detailed chemical kinetic reaction mechanism. Computed and experimental results are compared and used to help understand the chemical factors leading to engine knock in spark-ignited engines. The kinetic model reproduces observed variations in critical compression ratio with fuel molecular size and structure, provides intermediate product species concentrations in good agreement with observations, and gives insights into the kinetic origins of fuel octane sensitivity. Sequential computed engine cycles were found to lead to stable, non-igniting behavior for conditions below a critical compression ratio; to unstable, oscillating but nonigniting behavior in a transition region; and eventually to ignition as the compression ratio is steadily increased. This transition is related to conditions where a negative temperature coefficient of reaction exists, which has a significant influence on octane number and fuel octane sensitivity.
Download or read book Autoignition Chemistry of the Hexane Isomers An Experimental and Kinetic Modeling Study written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Autoignition Response of N butanol and Its Blend with Primary Reference Fuel Constituents of Gasoline written by and published by . This book was released on 2015 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: We study the influence of blending n-butanol on the ignition delay times of n-heptane and iso-octane, the primary reference fuels for gasoline. The ignition delay times are measured using a rapid compression machine, with an emphasis on the low-to-intermediate temperature conditions. The experiments are conducted at equivalence ratios of 0.4 and 1.0, for a compressed pressure of 20 bar, with the temperatures at the end of compression ranging from 613 K to 979 K. The effect of n-butanol addition on the development of the two-stage ignition characteristics for the two primary reference fuels is also examined. The experimental results are compared to predictions obtained using a detailed chemical kinetic mechanism, which has been obtained by a systematic merger of previously reported base models for the combustion of the individual fuel constituents. In conclusion, a sensitivity analysis on the base, and the merged models, is also performed to understand the dependence of autoignition delay times on the model parameters.
Download or read book An Experimental and Kinetic Modeling Study of the Combustion of N butane and Isobutane in an Internal Combustion Engine written by R. D. Wilk and published by . This book was released on 1990 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ignition and Heat Release Behaviour of Iso butanol and Gasoline Blended Fuels written by Christian Alexander Michelbach and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Homogeneous Charge Compression Ignition HCCI Engines written by Fuquan Zhao and published by SAE International. This book was released on 2003-01-01 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt: The homogeneous charge, compression-ignition (HCCI) combustion process has the potential to significantly reduce NOx and particulate emissions, while achieving high thermal efficiency and the capability of operating with a wide variety of fuels. This makes the HCCI engine an attractive technology that can ostensibly provide diesel-like fuel efficiency and very low emissions, which may allow emissions compliance to occur without relying on lean aftertreatment systems. A profound increase in the level of research and development of this technology has occurred in the last decade. This book gathers contributions from experts in both industry and academia, providing a basic introduction to the state-of-the-art of HCCI technology, a critical review of current HCCI research and development efforts, and perspective for the future. Chapters cover: Gasoline-Fueled HCCI Engines; Diesel-Fueled HCCI Engines; Alternative Fuels and Fuel Additives for HCCI Engines; HCCI Control and Operating Range Extension; Kinetics of HCCI Combustion; HCCI Engine Modeling Approaches.In addition to the extensive overview of terminology, physical processes, and future needs, each chapter also features select SAE papers (a total of 41 are included in the book), as well as a comprehensive list of references related to the subjects. Homogeneous Charge Compression Ignition (HCCI) Engines: Key Research and Development Issues provides a valuable base of information for those interested in learning about this rapidly-progressing technology which has the potential to enhance fuel economy and reduce emissions.
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 A Study of Autoignition in a Premixed Charge Internal Combustion Engine Using Comprehensive Chemical Kinetics written by Philip Michael Dimpelfeld and published by . This book was released on 1985 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Kinetic Modeling Study of the Pyrolysis and Oxidation of 1 5 hexadiene The Reactivity of Allylic Radicals and Their Role in the Formation of Aromatics written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Detailed Kinetic Modeling of Autoignition Chemistry written by Charles K. Westbrook and published by . This book was released on 1987 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Development of a Detailed Chemical Kinetic Mechanism for Diisobutylene and Comparison to Shock Tube Ignition Times written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: There is much demand for chemical kinetic models to represent practical fuels such as gasoline, diesel and aviation fuel. These blended fuels contain hundreds of components whose identity and amounts are often unknown. A chemical kinetic mechanism that would represent the oxidation of all these species with accompanying chemical reactions is intractable with current computational capabilities, chemical knowledge and manpower resources. The use of surrogate fuels is an approach to make the development of chemical kinetic mechanisms for practical fuels tractable. A surrogate fuel model consists of a small number of fuel components that can be used to represent the practical fuel and still predict desired characteristics of the practical fuel. These desired fuel characteristics may include ignition behavior, burning velocity, fuel viscosity, fuel vaporization, and fuel emissions (carbon monoxide, hydrocarbons, soot and nitric oxides). Gasoline consists of many different classes of hydrocarbons including n-alkanes, alkenes, iso-alkanes, cycloalkanes, cycloalkenes, and aromatics. One approach is to use a fuel surrogate that has a single component from each class of hydrocarbon in gasoline so that the unique molecular structure of each class is represented. This approach may lead to reliable predictions of many of the combustion properties of the practical fuel. In order to obtain a fuel surrogate mechanism, detailed chemical kinetic mechanisms must be developed for each component in the surrogate. In this study, a detailed chemical kinetic mechanism is developed for diisobutylene, a fuel intended to represent alkenes in practical fuels such as gasoline, diesel, and aviation fuel. The fuel component diisobutylene usually consists of a mixture of two conjugate olefins of iso-octane: 1- or 2-pentene, 2,4,4-trimethyl. Diisobutylene has a similar molecular structure to iso-octane, so that its kinetics offers insight into the effect of including a double bond in the carbon skeletal structure of iso-octane. There are few previous studies on diisobutylene. Kaiser et al. [1] examined the exhaust emission from a production spark ignition engine with neat diisobutylene and with it mixed with gasoline. They found the exhaust emissions of diisobutylene to be similar to that of iso-octane. They saw a significant increase in the amount of 2-methyl-1,3-butadiene measured in the exhaust of the engine. They also found appreciable amount of propene in the exhaust, but could not explain the source of this product as they did others in terms of C-C bond beta scission of alkyl radicals. Risberg et al. [2] studied a number of fuel blends to evaluate their autoignition quality for use in a homogeneous charge compression ignition engine, using diisobutylene to represent olefins in one of their test fuels. In this study, experiments on the shock tube ignition of both isomers of diisobutylene will be described. Then, the development of a detailed chemical kinetic mechanism for the two isomers of diisobutylene will be discussed.
Download or read book Fundamentals of Combustion Processes written by Sara McAllister and published by Springer Science & Business Media. This book was released on 2011-05-10 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Combustion Processes is designed as a textbook for an upper-division undergraduate and graduate level combustion course in mechanical engineering. The authors focus on the fundamental theory of combustion and provide a simplified discussion of basic combustion parameters and processes such as thermodynamics, chemical kinetics, ignition, diffusion and pre-mixed flames. The text includes exploration of applications, example exercises, suggested homework problems and videos of laboratory demonstrations
Download or read book Autoignition Behavior of Unsaturated Hydrocarbons in the Low and High Temperature Regions written by and published by . This book was released on 2010 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, numerical and experimental techniques are used to investigate the effect of the position of the double bond on the ignition properties of pentene and hexene linear isomers. A wide-range kinetic model for the oxidation of C5-C6 linear alkenes has been developed. Literature rapid compression machine data were used to validate the model at low temperatures and new shock tube experiments were performed in order to assess the behavior of the considered alkenes in the high temperature region. Some interesting inversions in the relative reactivity of the isomers were detected. The model successfully reproduced the measured behavior and allowed to explain the reason of these reactivity changes. The information gathered will be applied to the development of the kinetic mechanisms of larger unsaturated surrogate components.
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.
