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 Chemical Kinetic Modeling of Jet Fuel Surrogates written by Krithika Narayanaswamy and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Jet fuels, like typical transportation fuels, are mixtures of several hundreds of compounds belonging to different hydrocarbon classes. Their composition varies from one source to another, and only average fuel properties are known at best. In order to understand the combustion characteristics of the real fuels, and to address the problem of combustion control, computational studies using a detailed kinetic model to represent the real fuel, serves as a highly useful tool. However, the complexity of the real fuels makes it infeasible to simulate their combustion characteristics directly, requiring a simplified fuel representation to circumvent this difficulty. Typically, the real fuels are modeled using a representative surrogate mixture, i.e. a well-defined mixture comprised of a few components chosen to mimic the desired physical and chemical properties of the real fuel under consideration. Surrogates have been proposed for transportation fuels, including aviation fuels, and several kinetic modeling attempts for the proposed surrogates have also been made. However, (i) the fundamental kinetics of individual fuels, which make up the surrogate mixtures is not understood well, (ii) their combustion behavior at low through high temperatures has not been comprehensively validated, and this directly impacts the (iii) reliability of the multi-component reaction mechanism for a surrogate made up of these individual components. The present work is aimed at addressing the afore-mentioned concerns. The objective of this work is to develop a single, reliable kinetic model that can describe the oxidation of a few representative fuels, which are important components of transportation fuel surrogates, and thereby capture the specificities of the simpler, but still multi-component surrogates. The reaction mechanism is intended to well-represent the individual components as well as a multi-component surrogate for jet fuel made up of these fuel components. Further, this reaction mechanism is desired to be applicable at low through high temperatures, and be compact enough that chemical kinetic analysis is feasible. First, a representative compound for each of the major hydrocarbon classes found in the real jet fuel is identified. A surrogate for jet fuels is chosen to be comprised of n-dodecane (to represent normal alkanes), methylcyclohexane (to represent cyclic alkanes), and m-xylene (to represent aromatics). A Component Library approach is invoked for the development of a single, consistent, and reliable chemical scheme to accurately model this multi-component surrogate mixture. The chemical model is assembled in stages, starting with a base model and adding to it sub-mechanisms for the individual components of the surrogate, namely m- xylene, n-dodecane, and methylcyclohexane. The chemical model is validated comprehensively every time the oxidation pathways of a new component are incorporated into it and the experimental data is well captured by the simulations. In addition to the jet fuel surrogate, with the number of fuels described in the proposed reaction mechanism, a surrogate for the alternative Fischer-Tropsch fuels is also considered. Surrogates are defined for jet fuels and Fischer-Tropsch fuels by matching target properties important for combustion applications between the surrogate and the real fuel. The simulations performed using the proposed reaction mechanism, with the surrogates defined as fuels, are compared against global targets, such as ignition delays, flow reactor profiles, and flame speed measurements for representative jet fuels and Fischer-Tropsch fuels. The computations show promising agreement with these experimental data sets. The proposed reaction mechanism is well-suited to be used in real flow simulations of jet fuels. The proposed reaction mechanism has the ability to describe the kinetics of n- heptane, iso-octane, substituted aromatics, n-dodecane, and methylcyclohexane, all of which are important components of transportation fuel surrogates. Considering the large number of hydrocarbons whose kinetics are well described by this reaction mechanism, there are avenues for this reaction mechanism to be used to model other transportation fuels, such as gasoline, diesel, and alternative fuels, in addition to the jet and Fischer-Tropsch fuels discussed in the present study.

Download or read book Detailed Kinetic Modeling of Gasoline Surrogate Mixtures written by and published by . This book was released on 2009 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. It is generally agreed that their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. In this work, a recently revised version of the kinetic model by the authors is used to analyze the combustion behavior of several components relevant to gasoline surrogate formulation. Particular attention is devoted to linear and branched saturated hydrocarbons (PRF mixtures), olefins (1-hexene) and aromatics (toluene). Model predictions for pure components, binary mixtures and multi-component gasoline surrogates are compared with recent experimental information collected in rapid compression machine, shock tube and jet stirred reactors covering a wide range of conditions pertinent to internal combustion engines. Simulation results are discussed focusing attention on the mixing effects of the fuel components.

Download or read book Detailed Chemical Kinetic Modeling of Biofuels and Their Blends with Conventional Fuel Components written by Rupali Tripathi and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling and Simulation of Turbulent Combustion written by Santanu De and published by Springer. This book was released on 2017-12-12 with total page 663 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive review of state-of-the-art models for turbulent combustion, with special emphasis on the theory, development and applications of combustion models in practical combustion systems. It simplifies the complex multi-scale and nonlinear interaction between chemistry and turbulence to allow a broader audience to understand the modeling and numerical simulations of turbulent combustion, which remains at the forefront of research due to its industrial relevance. Further, the book provides a holistic view by covering a diverse range of basic and advanced topics—from the fundamentals of turbulence–chemistry interactions, role of high-performance computing in combustion simulations, and optimization and reduction techniques for chemical kinetics, to state-of-the-art modeling strategies for turbulent premixed and nonpremixed combustion and their applications in engineering contexts.

Download or read book Modeling of Chemical Reactions written by R.W. Carr and published by Elsevier. This book was released on 2007-09-04 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling of Chemical Reactions covers detailed chemical kinetics models for chemical reactions. Including a comprehensive treatment of pressure dependent reactions, which are frequently not incorporated into detailed chemical kinetic models, and the use of modern computational quantum chemistry, which has recently become an extraordinarily useful component of the reaction kinetics toolkit. It is intended both for those who need to model complex chemical reaction processes but have little background in the area, and those who are already have experience and would benefit from having a wide range of useful material gathered in one volume. The range of subject matter is wider than that found in many previous treatments of this subject. The technical level of the material is also quite wide, so that non-experts can gain a grasp of fundamentals, and experts also can find the book useful. A solid introduction to kinetics Material on computational quantum chemistry, an important new area for kinetics Contains a chapter on construction of mechanisms, an approach only found in this book

Download or read book A Kinetic Modeling Study on the Oxidation of Primary Reference Fuel Toluene Mixtures Including Cross Reactions Between Aromatics and Aliphatics written by and published by . This book was released on 2008 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed chemical kinetic model for the mixtures of Primary Reference Fuel (PRF: n-heptane and iso-octane) and toluene has been proposed. This model is divided into three parts; a PRF mechanism [T. Ogura et al., Energy & Fuels 21 (2007) 3233-3239], toluene sub-mechanism and cross reactions between PRF and toluene. Toluene sub-mechanism includes the low temperature kinetics relevant to engine conditions. A chemical kinetic mechanism proposed by Pitz et al. [Proc. the 2nd Joint Meeting of the U.S. Combust. Institute (2001)] was used as a starting model and modified by updating rate coefficients. Theoretical estimations of rate coefficients were performed for toluene and benzyl radical reactions important at low temperatures. Cross-reactions between alkane, alkene, and aromatics were also included in order to account for the acceleration by the addition of toluene into iso-octane recently found in the shock tube study of the ignition delay [Y. Sakai et al, SAE 2007-01-4014 (2007)]. Validations of the model were performed with existing shock tube and flow tube data. The model well predicts the ignition characteristics of toluene and PRF/Toluene mixtures under the wide range of temperatures (500-1700 K) and pressures (2-50 atm). It is found that reactions of benzyl radical with oxygen molecule determine the reactivity of toluene at low temperature. Although the effect of toluene addition to iso-octane is not fully resolved, the reactions of alkene with benzyl radical have the possibility to account for the kinetic interactions between PRF and toluene.

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 Kinetic Modeling of Gas Mixtures written by Lawrence Sirovich and published by Sagwan Press. This book was released on 2018-02-07 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.

Download or read book Chemical Kinetic Modeling of Advanced Transportation Fuels written by and published by . This book was released on 2009 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development of detailed chemical kinetic models for advanced petroleum-based and nonpetroleum based fuels is a difficult challenge because of the hundreds to thousands of different components in these fuels and because some of these fuels contain components that have not been considered in the past. It is important to develop detailed chemical kinetic models for these fuels since the models can be put into engine simulation codes used for optimizing engine design for maximum efficiency and minimal pollutant emissions. For example, these chemistry-enabled engine codes can be used to optimize combustion chamber shape and fuel injection timing. They also allow insight into how the composition of advanced petroleum-based and non-petroleum based fuels affect engine performance characteristics. Additionally, chemical kinetic models can be used separately to interpret important in-cylinder experimental data and gain insight into advanced engine combustion processes such as HCCI and lean burn engines. The objectives are: (1) Develop detailed chemical kinetic reaction models for components of advanced petroleum-based and non-petroleum based fuels. These fuels models include components from vegetable-oil-derived biodiesel, oil-sand derived fuel, alcohol fuels and other advanced bio-based and alternative fuels. (2) Develop detailed chemical kinetic reaction models for mixtures of non-petroleum and petroleum-based components to represent real fuels and lead to efficient reduced combustion models needed for engine modeling codes. (3) Characterize the role of fuel composition on efficiency and pollutant emissions from practical automotive engines.

Download or read book A COMBUSTION MODEL FOR MULTI COMPONENT FUELS BASED ON RELATIVE REACTIVITY AND MOLECULAR STRUCTURE written by and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : A reliable multi-component surrogate fuel model needs to be able to represent both physical properties and chemical kinetics of a real fuel. However, enhancing the fidelity of a model with detailed description of physical and chemical behavior of all fuel components found in real fuels is limited by the prohibitive computational load to calculate the combustion chemistry of the fuel. Hence, it is desirable to achieve computational efficiency by reducing the number of chemical surrogates at the minimum expense of prediction accuracy. The objective of this work is to develop a model that can simulate the oxidation of multi-component fuels by representing the ignition characteristics of physical surrogate components with fewer chemical surrogates and achieve both computational efficiency and prediction accuracy. The main advantage of the model, called the Reactivity-Adjustment (ReAd) combustion model, is to accurately predict the reactivity of the physical surrogate components that the reaction mechanisms of which are not included in the reaction kinetics model employed in the simulation. The reactivity variation of local mixtures with different compositions is modeled by adjusting the reaction rate constants of selected control-reactions in the reaction mechanism of the representative chemical surrogates. An initial version of the model has been developed employing a single chemical surrogate to represent the combustion of diesel fuel which is modeled as multiple surrogate components to capture the physical properties of the real fuel. The model was extended to consider two more chemical surrogate components to represent the ignition characteristics of other chemical families than n-alkanes. This enabled to avoid the excessive adjustment of reaction rate constants that were necessary when a single chemical surrogate is used to represent the oxidation kinetics of entire multi-component fuels. The model was extensively tested for simulating oxidation processes of many fuels with a variety of fuel reactivity and in various combustion regimes. The results demonstrated that excellent accuracy of the ignition/combustion prediction was achieved while ensuring computational efficiency.

Download or read book Kinetic modelling of gas mixtures written by Marlies Pirner and published by BoD – Books on Demand. This book was released on 2018-07-10 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the kinetic modelling of gas mixtures. It extends the existing literature in mathematics for one species of gas to the case of gas mixtures. This is more realistic in applications. The presented model for gas mixtures is proven to be consistent meaning it satisfies the conservation laws, it admits an entropy and an equilibrium state. Furthermore, we can guarantee the existence, uniqueness and positivity of solutions. Moreover, the model is used for different applications, for example in plasma physics, for fluids with a small deviation from equilibrium and in the case of polyatomic gases.

Download or read book Advances in Compression Ignition Natural Gas Diesel Dual Fuel Engines written by Hongsheng Guo and published by Frontiers Media SA. This book was released on 2021-03-23 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 2023 Asia Pacific International Symposium on Aerospace Technology APISAT 2023 Proceedings written by Song Fu and published by Springer Nature. This book was released on with total page 1975 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 Kinetic Modeling of Toluene Oxidation for Surrogate Fuel Applications written by and published by . This book was released on 2009 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: New environmental issues, like the effect of combustion-generated greenhouse gases, provide motivation to better characterize oxidation of hydrocarbons. Transportation, in particular, significantly contributes to energy consumption and CO2 emissions. Kinetic studies about the combustion of fuels under conditions typical of internal combustion engines provides important support to improve mechanism formulation and to eventually provide better computational tools that can be used to increase the engine performance. It is foreseeable that at least in the next 30 years the main transportation fuels will be either gasoline or diesel. Unfortunately, these fuels are very complex mixtures of many components. Moreover, their specifications and performance requirements significantly change the composition of these fuels: gasoline and diesel mixtures are different if coming from different refineries or they are different from winter to summer. At the same time a fuel with a well defined and reproducible composition is needed for both experimental and modeling work. In response to these issues, surrogate fuels are proposed. Surrogate fuels are defined as mixtures of a small number of hydrocarbons whose relative concentrations is adjusted in order to approximate the chemical and physical properties of a real fuel. Surrogate fuels are then very useful both for the design of reproducible experimental tests and also for the development of reliable kinetic models. The primary reference fuels (PRF) are a typical and old example of surrogate fuel: n-heptane and iso-octane mixtures are used to reproduce antiknock propensity of complex mixtures contained in a gasoline. PRFs are not able to surrogate gasoline in operating conditions different from standard ones and new surrogates have been recently proposed. Toluene is included in all of them as a species able to represent the behavior of aromatic compounds. On the other side, the toluene oxidation chemistry is not so well established and uncertainties still remain in the mechanism. This is especially true in the low temperature regime (

Download or read book Kinetic Modeling of Gas Mixtures Primary Source Edition written by Lawrence Sirovich and published by Nabu Press. This book was released on 2013-10 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a reproduction of a book published before 1923. This book may have occasional imperfections such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact, or were introduced by the scanning process. We believe this work is culturally important, and despite the imperfections, have elected to bring it back into print as part of our continuing commitment to the preservation of printed works worldwide. We appreciate your understanding of the imperfections in the preservation process, and hope you enjoy this valuable book.