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Modeling And Experimental Investigation Of Methylcyclohexane Ignition In A Rapid Compression Machine
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Book Synopsis Modeling and Experimental Investigation of Methylcyclohexane Ignition in a Rapid Compression Machine by : W. J. Pitz
Download or read book Modeling and Experimental Investigation of Methylcyclohexane Ignition in a Rapid Compression Machine written by W. J. Pitz and published by . This book was released on 2005 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experimental and Kinetic Modeling Study of Cyclohexane and Its Mono-alkylated Derivatives Combustion by : Zhandong Wang
Download or read book Experimental and Kinetic Modeling Study of Cyclohexane and Its Mono-alkylated Derivatives Combustion written by Zhandong Wang and published by Springer. This book was released on 2018-01-23 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis investigates the combustion chemistry of cyclohexane, methylcyclohexane, and ethylcyclohexane on the basis of state-of-the-art synchrotron radiation photoionization mass spectrometry experiments, quantum chemistry calculations, and extensive kinetic modeling. It explores the initial decomposition mechanism and distribution of the intermediates, proposes a novel formation mechanism of aromatics, and develops a detailed kinetic model to predict the three cycloalkanes’ combustion properties under a wide range of conditions. Accordingly, the thesis provides an essential basis for studying much more complex cycloalkanes in transport fuels and has applications in engine and fuel design, as well as emission control.
Book Synopsis An Investigation of Phase-change Effects During Rapid Compression Machine Experiments by : Colin Banyon
Download or read book An Investigation of Phase-change Effects During Rapid Compression Machine Experiments written by Colin Banyon and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapid compression machines (RCMs) are well characterized laboratory scale devices capable of achieving internal combustion (IC) engine relevant thermodynamic environments. These machines are often used to collect ignition delay times as targets for gas-phase chemical kinetic fuel autoigntion models. Modern RCMs utilize creviced piston(s) to improve charge homogeneity and allow for an adequate validation of detailed chemistry mechanisms against experiments using computationally efficient, homogeneous reactor models (HRMs). Conventionally, experiments are preformed by introducing a premixed gas of fuel + oxidizer + diluent into the machine, which is compressed volumetrically via a piston. Experiments investigating low-vapor pressure fuels (e.g. diesels, biodiesels, jet fuels, etc.) and surrogates can be conducted by preheating both the charge as well as the machine. This method of fuel loading can lead to pretest fuel pyrolysis as well as machine seal degradation. Under some conditions loading a fuel aerosol of finely atomized liquid droplets in an oxidizer + diluent bath gas (i.e. wet compression) has been suggested to extend the capabilities of RCM experiments to involatile fuels. This work investigates phase-change effects during RCM experiments, especially for aerosol-fueling conditions, while the methodology can be applied to gas-phase fuel experiments where fuel condensation can occur at the compressed conditions within the boundary layer region. To facilitate this study a reduced-order, physics-based model is used. This work highlights important machine-scale influences not investigated in previous work, and provides additional detail concerning an aerosol RCM{u2019}s capabilities and limitations. A transient formulation is developed for the multi-phase transport within the RCM reaction chamber as well as the flow to the piston crevice region during both the compression and delay periods. The goal of this work is threefold. First, an a priori knowledge of the stratification present under various conditions can help determine an optimum machine geometry so that discrepancies between experimental data sets and 0D kinetics simulations are minimized for involatile fuels. Second, the model is computationally tractable to prescribe heat loss rates to an HRM during simulations of experiments so that physical effects can be incorporated into simulations using detailed chemistry. Finally, heat loss rates that are prescribed to the HRM are only a function of machine geometry, and are independent of ad hoc and empirically derived fits that vary between facilities. Thus a more adequate comparison of data between RCM facilities and with existing literature can be made.
Book Synopsis Gasoline Surrogate Modeling of Gasoline Ignition in a Rapid Compression Machine and Comparison to Experiments by :
Download or read book Gasoline Surrogate Modeling of Gasoline Ignition in a Rapid Compression Machine and Comparison to Experiments written by and published by . This book was released on 2011 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of gasoline in homogeneous charge compression ignition engines (HCCI) and in duel fuel diesel - gasoline engines, has increased the need to understand its compression ignition processes under engine-like conditions. These processes need to be studied under well-controlled conditions in order to quantify low temperature heat release and to provide fundamental validation data for chemical kinetic models. With this in mind, an experimental campaign has been undertaken in a rapid compression machine (RCM) to measure the ignition of gasoline mixtures over a wide range of compression temperatures and for different compression pressures. By measuring the pressure history during ignition, information on the first stage ignition (when observed) and second stage ignition are captured along with information on the phasing of the heat release. Heat release processes during ignition are important because gasoline is known to exhibit low temperature heat release, intermediate temperature heat release and high temperature heat release. In an HCCI engine, the occurrence of low-temperature and intermediate-temperature heat release can be exploited to obtain higher load operation and has become a topic of much interest for engine researchers. Consequently, it is important to understand these processes under well-controlled conditions. A four-component gasoline surrogate model (including n-heptane, iso-octane, toluene, and 2-pentene) has been developed to simulate real gasolines. An appropriate surrogate mixture of the four components has been developed to simulate the specific gasoline used in the RCM experiments. This chemical kinetic surrogate model was then used to simulate the RCM experimental results for real gasoline. The experimental and modeling results covered ultra-lean to stoichiometric mixtures, compressed temperatures of 640-950 K, and compression pressures of 20 and 40 bar. The agreement between the experiments and model is encouraging in terms of first-stage (when observed) and second-stage ignition delay times and of heat release rate. The experimental and computational results are used to gain insight into low and intermediate temperature processes during gasoline ignition.
Book Synopsis Kinetic Modeling of Hydrocarbon Autoignition at Low and Intermediate Temperatures in a Rapid Compression Machine by :
Download or read book Kinetic Modeling of Hydrocarbon Autoignition at Low and Intermediate Temperatures in a Rapid Compression Machine written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A computer model is used to examine oxidation of hydrocarbon fuels in a rapid compression machine. For one of the fuels studied, n-heptane, significant fuel consumption is computed to take place during the compression stroke under some operating conditions, while for the less reactive n-pentane, no appreciable fuel consumption occurs until after the end of compression. The third fuel studied, a 60 PRF mixture of iso-octane and n-heptane, exhibits behavior that is intermediate between that of n-heptane and n-pentane. The model results indicate that computational studies of rapid compression machine ignition must consider fuel reaction during compression in order to achieve satisfactory agreement between computed and experimental results.
Book Synopsis Encyclopedia of Automotive Engineering by :
Download or read book Encyclopedia of Automotive Engineering written by and published by John Wiley & Sons. This book was released on 2015-03-23 with total page 3888 pages. Available in PDF, EPUB and Kindle. Book excerpt: Erstmals eine umfassende und einheitliche Wissensbasis und Grundlage für weiterführende Studien und Forschung im Bereich der Automobiltechnik. Die Encyclopedia of Automotive Engineering ist die erste umfassende und einheitliche Wissensbasis dieses Fachgebiets und legt den Grundstein für weitere Studien und tiefgreifende Forschung. Weitreichende Querverweise und Suchfunktionen ermöglichen erstmals den zentralen Zugriff auf Detailinformationen zu bewährten Branchenstandards und -verfahren. Zusammenhängende Konzepte und Techniken aus Spezialbereichen lassen sich so einfacher verstehen. Neben traditionellen Themen des Fachgebiets beschäftigt sich diese Enzyklopädie auch mit "grünen" Technologien, dem Übergang von der Mechanik zur Elektronik und den Möglichkeiten zur Herstellung sicherer, effizienterer Fahrzeuge unter weltweit unterschiedlichen wirtschaftlichen Rahmenbedingungen. Das Referenzwerk behandelt neun Hauptbereiche: (1) Motoren: Grundlagen; (2) Motoren: Design; (3) Hybrid- und Elektroantriebe; (4) Getriebe- und Antriebssysteme; (5) Chassis-Systeme; (6) Elektrische und elektronische Systeme; (7) Karosserie-Design; (8) Materialien und Fertigung; (9) Telematik. - Zuverlässige Darstellung einer Vielzahl von Spezialthemen aus dem Bereich der Automobiltechnik. - Zugängliches Nachschlagewerk für Jungingenieure und Studenten, die die technologischen Grundlagen besser verstehen und ihre Kenntnisse erweitern möchten. - Wertvolle Verweise auf Detailinformationen und Forschungsergebnisse aus der technischen Literatur. - Entwickelt in Zusammenarbeit mit der FISITA, der Dachorganisation nationaler Automobil-Ingenieur-Verbände aus 37 Ländern und Vertretung von über 185.000 Ingenieuren aus der Branche. - Erhältlich als stets aktuelle Online-Ressource mit umfassenden Suchfunktionen oder als Print-Ausgabe in sechs Bänden mit über 4.000 Seiten. Ein wichtiges Nachschlagewerk für Bibliotheken und Informationszentren in der Industrie, bei Forschungs- und Schulungseinrichtungen, Fachgesellschaften, Regierungsbehörden und allen Ingenieurstudiengängen. Richtet sich an Fachingenieure und Techniker aus der Industrie, Studenten höherer Semester und Studienabsolventen, Forscher, Dozenten und Ausbilder, Branchenanalysen und Forscher.
Book Synopsis Mathematical Modelling of Gas-Phase Complex Reaction Systems: Pyrolysis and Combustion by :
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
Book Synopsis Homogeneous Charge Compression Ignition Engines, 2007 by :
Download or read book Homogeneous Charge Compression Ignition Engines, 2007 written by and published by . This book was released on 2007 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experiments and Modeling of the Autoignition of Methyl Pentanoate at Low to Intermediate Temperatures and Elevated Pressures in a Rapid Compression Machine by :
Download or read book Experiments and Modeling of the Autoignition of Methyl Pentanoate at Low to Intermediate Temperatures and Elevated Pressures in a Rapid Compression Machine written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Effect of Vortex Roll-up and Crevice Mass Flow on Ignition in a Rapid Compression Machine by : Mickael Chomier
Download or read book Effect of Vortex Roll-up and Crevice Mass Flow on Ignition in a Rapid Compression Machine written by Mickael Chomier and published by . This book was released on 2013 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this thesis is to understand the influence of the non-ideal effects in Rapid Compression Machines (RCM), namely the vortex roll-up and mass flow into the crevice, on autoignition. The effect of the vortex roll-up is studied computationally using CFD simulations of autoignition in a RCM. Whereas, the effect of the crevice mass flow is investigated experimentally by studying isooctane autoignition. Over the last two decades, experimental data of the nature of species evolution profiles and ignition delays from RCMs has been used to develop and validate chemical kinetic mechanisms at low-to-intermediate temperatures and elevated pressures. A significant portion of this overall dataset is from RCMs that had not employed a creviced piston to contain the roll-up vortex. The detrimental influence of the roll-up vortex and the thermokinetic interactions due to the resulting temperature non-homogeneity during the negative temperature coefficient (ntc) regime have been documented in the literature. However, the adequacy of the homogeneous modeling of RCMs without creviced pistons during reactive conditions has not been investigated. In this work, computational fluid dynamics simulations of an RCM without a creviced piston are conducted for autoignition of n-heptane over the entire ntc regime over a range of compressed pressures from 5 to 18 bar. The results from the CFD simulations highlight the non-homogeneity of autoignition and reveal significant quantitative discrepancy in comparison to homogeneous modeling, particularly for the hot ignition delay in the ntc regime. Specifically, the roll-up vortex induced temperature non-homogeneity leads to diminution of the ntc behavior. The experimental data from RCMs without creviced piston needs to be taken with caution for quantitative validation and refinement of kinetic mechanism, particularly at conditions when ntc behavior is highly pronounced. Rapid Compression Machines (RCMs) often employ creviced pistons to suppress the formation of the roll-up vortex. However, the use of a creviced piston promotes mass flow into the crevice when heat release takes place in the main combustion chamber. This multi-dimensional effect is not accounted for in the prevalent volumetric expansion approach for modeling RCMs. The method of crevice containment, on the other hand, avoids post-compression mass flow into the crevice. In order to assess the effect of the crevice mass flow on ignition in a RCM, experiments were conducted for autoignition of isooctane in a RCM with creviced piston in the temperature range of 680-940 K and at compressed pressures of ~15.5 and 20.5 bar in two ways. In one situation, post-compression mass flow to the crevice is avoided by crevice containment and in other it is allowed. Experiments show that the crevice mass flow can lead to significantly longer ignition delays. Experimental data from both scenarios is modeled using adiabatic volumetric expansion approach and an available kinetic mechanism. The simulated results show less pronounced effect of crevice mass flow on ignition delay and highlight the deficiency of the volumetric expansion method owing to its inability to describe coupled physical-chemical processes in the presence of heat release. Results indicate that it is important to include crevice mass flow in the physical model for improved modeling of experimental data from RCMs for consistent interpretation of chemical kinetics. The use of crevice containment, however, avoids the issue of mass flow altogether and offers an alternative and sound approach.
Book Synopsis A Rapid Compression Machine Modelling Study of the Heptane Isomers by :
Download or read book A Rapid Compression Machine Modelling Study of the Heptane Isomers written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Previously we have reported on the combustion behavior of all nine isomers of heptane in a rapid compression machine (RCM) with stoichiometric fuel and ''air'' mixtures at a compressed gas pressure of 15 atm. The dependence of autoignition delay times on molecular structure was illustrated. Here, we report some additional experimental work that was performed in order to address unusual results regarding significant differences in the ignition delay times recorded at the same fuel and oxygen composition, but with different fractions of nitrogen and argon diluent gases. Moreover, we have begun to simulate these experiments with detailed chemical kinetic mechanisms. These mechanisms are based on previous studies of other alkane molecules, in particular, n-heptane and iso-octane. We have focused our attention on n-heptane in order to systematically redevelop the chemistry and thermochemistry for this C-- isomer with the intention of extending our greater knowledge gained to the other eight isomers. The addition of new reaction types, that were not included previously, has had a significant impact on the simulations, particularly at low temperatures.
Book Synopsis Methylcyclohexane Ignition Delay Times Under a Wide Range of Conditions by : Aditya Nagulapalli
Download or read book Methylcyclohexane Ignition Delay Times Under a Wide Range of Conditions written by Aditya Nagulapalli and published by . This book was released on 2015 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last century, our dependence on oil has increased rapidly and is projected to increase for several decades. There is a critical need to improve the design of the combustion chamber for different kinds of engines to reduce fuel consumption. Chemical kinetics of the fuel plays an important role in reducing emissions and improving engine efficiency. Studying single components of a conventional fuel allows a fuller understanding of the physical and chemical behavior of the real fuel. Many studies have been conducted on all classes of hydrocarbons, with the exception of cycloalkanes. Only a few studies exist on cycloalkanes, which is an important class of hydrocarbons. Methylcyclohexane (MCH), which is widely used as a surrogate to represent the cycloalkane portion of a fuel, was chosen as the subject of this study. The shock tube is an established tool used for measuring the ignition delay, and was used as the experimental apparatus. Ignition delay was measured using the end-plate pressure rise, the OH* and CH* chemiluminescence and white light emission. In addition, experimental results were compared with kinetic modeling data using detailed MCH mechanisms developed by Pitz et al. and Orme et al. Different modeling approaches, such as constant volume and internal energy (with and without experimental pressure profiles) and constant pressure, were used to validate the models by comparing against experimental ignition delay data. It was observed that the equivalence ratio affects the ignition delay time. For the lower argon concentration (Ar = 93%) and higher pressure (P ~ 16 atm), ignition delay times were longest for rich conditions. Additionally, they were shorter at lower temperatures (T = 1250 K) for stoichiometric conditions in comparison to lean values, but the opposite trend was observed at the higher temperatures (T > 1250 K). Ignition delay times of stoichiometric mixtures were longer than lean mixtures across the studied temperature range for low pressure (P = 2 atm) and argon concentration (Ar = 93%), as well as high pressure (P ~ 16 atm) and argon concentration (Ar = 98%). The Orme et al. model using the approach of constant U,V assumption with experimental pressure profile showed a better agreement with experimental results at low temperatures than the approach without experimental pressure profile. Both models and approaches underestimate the experimental ignition delay times at high temperatures.
Book Synopsis A Rapid Compression Machine with the Novel Concept of Crevice Containment by : Anil Bhari
Download or read book A Rapid Compression Machine with the Novel Concept of Crevice Containment written by Anil Bhari and published by . This book was released on 2010 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapid Compression Machines (RCMs) typically incorporate creviced pistons to suppress the formation of the roll-up vortex. The use of a creviced piston, however, can enhance other multi-dimensional effects inside the RCM due to the crevice zone being at a lower temperature than the main reaction chamber. In this work, such undesirable effects of the creviced piston are first highlighted through computational fluid dynamics simulations of n-heptane ignition in an RCM. Specifically, the results show that in an RCM with a creviced piston, additional mass flow takes place from the main combustion chamber to the crevice zone during the first-stage ignition. This phenomenon is not captured by the conventional zero-dimensional modeling approaches. Consequently, a novel approach of 'crevice containment' is introduced and evaluated. According to this approach, in order to avoid the undesirable effects of the creviced piston, the crevice zone is separated from the main reaction chamber at the end of compression. The computational results with this novel approach show significant improvement in the fidelity of the zero-dimensional modeling in terms of predicting the overall ignition delay and pressure rise in the first-stage ignition. In addition, this approach also offers other advantages, namely a reduction in the rate of post-compression pressure drop and improved data during species sampling experiments. An RCM is subsequently designed and successfully fabricated with the feature of 'crevice containment' for the purpose of chemical kinetics studies at elevated pressures and temperatures. Characterization experiments for the newly built RCM show that the operation of the RCM is free from any vibrations, allows fast compression (22 ms), compressed pressures up to 100 bar and the experimental data obtained is highly reproducible. Using this facility, autoignition investigations are conducted for Hydrogen at a pressure of 50 bar. The experiments are modeled using the kinetic mechanism of O'Conaire et al. (2004). Results showed that the mechanism of O'Conaire et al. agree very well with the experimental data.
Book Synopsis Data Base Generation and Modeling of Homogeneous Charge Compression Ignition Using a Rapid Compression Machine by : Ferran Alberto Ayala
Download or read book Data Base Generation and Modeling of Homogeneous Charge Compression Ignition Using a Rapid Compression Machine written by Ferran Alberto Ayala and published by . This book was released on 2001 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experiments on the Effects of Dilution and Fuel Composition on Ignition of Gasoline and Alternative Fuels in a Rapid Compression Machine by : Prasanna Chinnathambi
Download or read book Experiments on the Effects of Dilution and Fuel Composition on Ignition of Gasoline and Alternative Fuels in a Rapid Compression Machine written by Prasanna Chinnathambi and published by . This book was released on 2019 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the first part of this work, ignition of methane-air mixtures under excess air dilution is studied. When excess air is used in SI engine operation, thermal efficiency is increased due to increase in compression ratio together with reduced pumping and heat loses. However, stable operation with excess air is challenging due to poor flammability of the resulting diluted mixture. Hence in order to achieve stable and complete combustion a turbulent jet ignition (TJI) system is used to improve combustion of lean methane-air mixtures. Various nozzle designs and operating strategies for a TJI system were tested in a rapid compression machine. 10-90% burn duration measurements were useful in assessing the performance of the nozzle designs while the 0-10% burn durations indicated if optimal air-fuel ratio is achieved within the pre-chamber at the time of ignition. The results indicated that distributed-jets TJI system offered faster and stable combustion while the concentrated-jets TJI system offered better dilution tolerance.Knock in a SI engine occurs due to autoignition of the end gas mixture and typically occurs in the negative temperature coefficient (NTC) region of the fuel-air mixture. Dilution of intake charge with cold exhaust recirculation gases (EGR) reduces combustion temperatures and decreases mixture reactivity thereby reducing knocking tendency. This enables optimal spark timings to be used, thereby increasing efficiency of SI engines which would otherwise be knock limited. Effect of cold EGR dilution is studied in the RCM by measuring the autoignition delay times of gasoline and gasoline surrogate mixtures diluted with varying levels of CO2. The autoignition experiments in the RCM were performed using a novel direct test chamber (DTC) charge preparation approach. The DTC approach enabled mixture preparation directly within the combustion chamber and eliminated the need for mixing tanks. Effect of CO2 dilution in retarding the autoignition delay times was more pronounced in the NTC region, while it was weaker in the low temperature and high temperature regions. The retarding effect was found to be dependent on both the octane number and the fuel composition of the gasoline being studied.Finally, the effect of substituting ethanol(biofuel) in gasoline surrogates for up to 40% by volume is studied. Ethanol is an octane booster, but it blends antagonistically with aromatics such as toluene and synergistically with alkanes with respect to the resulting octane number of the blends. In order to study this blending effect, two gasoline surrogates containing only alkanes (PRF), and alkanes with large amounts of toluene (TRF) are blended with varying levels of ethanol. The ignition delay times of the resulting mixtures are measured in a rapid compression machine and kinetic analysis was carried out using numerical simulations. The kinetic analysis revealed that ethanol controlled the final stages of ignition for the PRF blends when more than 10% by volume of ethanol is present. However, in the TRF blends, toluene controlled the ignition until mole fractions of ethanol became higher than the toluene indicating the reason for the antagonistic blending nature. It was found that the RON values of the resulting blends matched the trend of the ignition delay times recorded at 740K and 21 bar compressed conditions. This enables qualitative assessment of the RON numbers for new biofuel blends by measuring their ignition delay times in the RCM.
Book Synopsis The Effects of Pressure, Temperature and Concentration on the Reactivity of Alkanes ; Experiments and Modeling in a Rapid Compression Machine by :
Download or read book The Effects of Pressure, Temperature and Concentration on the Reactivity of Alkanes ; Experiments and Modeling in a Rapid Compression Machine written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments in a rapid compression machine have examined the influences of variations in pressure, temperature, and equivalence ratio on the autoignition of n-pentane. Equivalence ratios included values from 0.5 to 2.0, compressed gas initial temperatures were varied between 675K and 980K, and compresed gas initial pressures varied from 8 to 20 bar. Numerical simulations of the same experiments were carried out using a detailed chemical kinetic reaction mechanism. The results are interpreted in terms of a low temperature oxidation mechanism involving addition of molecular oxygen to alkyl and hydroperoxyalkyl radicals. Idealized calculations are reported which identify the major reaction paths at each temperature. Results indicate that in most cases, the reactive gases experience a two-stage autoigni tion. The first stage follows a low temperature alkylperoxy radical isomerization pathway that is effectively quenched when the temperature reaches a level where dissociation reactions of alkylperoxy and hydroperoxyalkylperoxy radicals are more rapid than the reverse addition steps. The second stage is controlled by the onset of dissociation of hydrogen peroxide. Results also show that in some cases, the first stage ignition takes place during the compression stroke in the rapid compression machine, making the interpretation of the experiments somewhat more complex than generally assumed. At the highest compression temperatures achieved, little or no first stage ignition is observed.
Book Synopsis Advanced Rapid Compression Machine Test Methods and Surrogate Fuel Modeling for Bio-derived Jet and Diesel Fuel Autoignition by : Casey M. Allen
Download or read book Advanced Rapid Compression Machine Test Methods and Surrogate Fuel Modeling for Bio-derived Jet and Diesel Fuel Autoignition written by Casey M. Allen and published by . This book was released on 2012 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
