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 The Autoignition Chemistries of Primary Reference Fuels Olefin paraffin Binary Mixtures and Non linear Octane Blending written by William R. Leppard and published by . This book was released on 1992 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flammability and Autoignition of Hydrocarbon Fuels Under Static and Dynamic Conditions written by J. M. Kuchta and published by . This book was released on 1962 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Autoignition Study of Ethanol and Heptane in a Rapid Compression Machine written by Varun Anthony Davies and published by . This book was released on 2015 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Practical fuels are a complex mixture of thousands of hydrocarbon compounds, making it challenging and difficult to study their combustion behavior. It's generally agreed that in order to study these complex practical fuels a much simpler approach of studying simple fuel surrogates containing limited number of components is more feasible. Ethanol and n-heptane have been studied as primary reference fuels in the surrogate study of gasoline and diesel over the past few decades. The objective of the following thesis has been to study the autoignition characteristics of ethanol and n-heptane and validate chemical kinetic mechanisms. The validation of a chemical kinetic mechanism provides a deeper insight into the combustion behavior of the fuels which can be further used to study advanced combustion concepts. Experiments have been conducted on the rapid compression machine (RCM) and validated against mechanisms from literature study. Rapid compression machines have been primarily used to study chemical kinetics at low to intermediate temperatures and high pressures for their accuracy and reproducibility. For the following study experiments span over a range of temperature (650-1000 K), pressure (10, 15 and 20 bar) and equivalence ratio ([phi]=0.3, 0.5, 1). Experimental data based on the adiabatic volumetric expansion approach have been modeled numerically using the Sandia SENKIN code in conjunction with CHEMKIN. Experiments have been primarily focused on validating kinetic mechanisms at low to intermediate temperatures and elevated pressures. Ignition delay time data from experiments have been deduced based on the pressure and time histories. A brute sensitivity and flux analysis has been performed to reveal the key sensitive reactions and the dominant reaction pathways followed under the present experimental conditions. Improvements have been suggested and discrepancies noted in order to develop a valid chemical kinetic mechanism. Under the present experimental conditions for the study of ethanol, reactions involving hydroperoxyl radicals, namely C2H5OH+HȮ2 and CH3CHO+ HȮ2 as well as the formation of H2O2 from HȮ2 radical and its subsequent decomposition have been found to be sensitive. Based on the following, improvements and developements have been suggested to increase the accuracy and predictability of the mechanisms studied. Ignition delay data from experiments have been compared against those obtained from the mechanism used in the study for n-heptane. Discrepancies have been found in the low temperature region, with the mechanism under predicting the first ignition delay. The causes for the discrepancy have been noted to be due to the NTC behaviour exhibited during the two stage ignition of n-heptane. At low temperatures the reaction pathway proceeded by chain branching mainly due to the ketohydroperoxide species reaction pathway has been analysed. As the temperature of the reaction increases the reaction pathway is dominated by the ȮOH species propagation resulting in the formation of conjugate olefins and [Beta]-decomposition products, a further investigation of which can help improve the predictability of the mechanism.

Download or read book Autoignition and Emissions related Chemistry of Primary Reference Fuels and Gasoline Components written by Charles V. Callahan and published by . This book was released on 1995 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ignition Behavior of Gasolines and Surrogate Fuels in Low Temperature Combustion Strategies written by Vickey Kalaskar and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation discusses the results from three different studies aimed at understanding the importance of fuel chemical structure during low temperature combustion (LTC) strategies, like homogeneous charge compression ignition (HCCI) and partially premixed combustion (PPC) employed in internal combustion (IC) engines wherein the focus is on high octane fuels. Boosted intake air operation combined with exhaust gas recirculation, internal as well as external, has become a standard path for expanding the load limits of IC engines employing LTC strategies mentioned above as well as conventional diesel and spark ignition (SI) engines. However, the effects of fuel compositional variation have not been fully explored. The first study focusses on three different fuels, where each of them were evaluated using a single cylinder boosted HCCI engine using negative valve overlap. The three fuels investigated were: a regular grade gasoline (RON = 90.2), 30% ethanol-gasoline blend (E30, RON = 100.3), and 24% iso-butanol-gasoline blend (IB24, RON = 96.6). Detailed sweeps of intake manifold pressure (atmospheric to 250 kPaa), EGR (0 -- 25% EGR), and injection timing were conducted to identify fuel-specific effects. While significant fuel compositional differences existed, the results showed that all these fuels achieved comparable operation with minor changes in operational conditions. Further, it was shown that the available enthalpy from the exhaust would not be sufficient to satisfy the boost requirements at higher load operation by doing an analysis of the required turbocharger efficiency. While the first study concentrated on load expansion of HCCI, it is important to mention that controlling LTC strategies is difficult under low load or idle operating conditions. To ensure stable operation, fuel injection in the negative valve overlap (NVO) is used as one of method of achieving combustion control. However the combustion chemistry under high temperature and fuel rich conditions that exist during the NVO have not been previously explored. The second study focused on examining the products of fuel rich chemistry as a result of fuel injection in the NVO. In this study, a unique six stroke cycle was used to segregate the exhaust from the NVO and to study the chemistry of the range of fuels injected during NVO under low oxygen conditions. The fuels investigated were methanol, ethanol, iso-butanol, and iso-octane. It was observed that the products of reactions under NVO conditions were highly dependent on the injected fuel's structure with iso-octane producing less than 1.5% hydrogen and methanol producing more than 8%. However a weak dependence was observed on NVO duration and initial temperature, indicating that NVO reforming was kinetically limited. Finally, the experimental trends were compared with CHEMKIN (single zone, 0-D model) predictions using multiple kinetic mechanism that were readily available through literature. Due to the simplicity of the model and inadequate information on the fuel injection process, the experimental data was not modeled well with the mechanisms tested. Some of the shortcomings of the 0-D model were probably due to the model ignoring temperature and composition spatial inhomogeneities and evaporative cooling from fuel vaporization.Though the results from the NVO injection and boosted NVO-HCCI studies are enlightening, the fundamentals of the autoignition behavior of gasoline, alcohols, and their mixtures are not entirely understood despite the interest in high octane fuels in compression engines from a point of view of better thermal efficiency. The third study focused on higher octane blends consisting of binary and ternary mixtures of n-heptane and/or iso-octane, and a fuel of interest. These fuels of interest were toluene, ethanol, and iso-butanol. In this study, the autoignition of such blends is studied under lean conditions ([phi] = 0.25) with varying intake pressure (atmospheric to 3 bar, abs) and at a constant intake temperature of 155 °C. The blends consisted of varying percentages of fuels of interest and their research octane number (RON) approximately estimated at 100 and 80. For comparison, neat iso-octane was selected as RON 100 fuel and PRF 80 blend was selected as RON 80 fuel. It was observed that the blends with a higher percentage of n-heptane showed a stronger tendency to autoignite at lower intake pressures. However, as the intake pressure was increased, the non-reactive components, in this case, the higher octane blend components (toluene, ethanol, and iso-butanol), reduced this tendency subsequently delaying the critical compression ratio (CCR) of the blends. The heat release analysis revealed that the higher octane components in the blends reduced the low temperature reactivity of n-heptane and iso-octane. GC-MS and GC-FID analysis of the partially compressed fuel also indicated that the higher octane components did affect the conversion of the more reactive components, n-heptane and iso-octane, into their partially oxidized branched hydrocarbons in the binary/ternary blends, and reduced the overall reactivity which resulted in a delayed CCR at higher intake pressures.

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 The Effect of Nitric Oxide on Autoignition of a Primary Reference Fuel Blend in a Motored Engine written by S. K. Prabhu and published by . This book was released on 1993 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Alcohol as an Alternative Fuel for Internal Combustion Engines written by Pravesh Chandra Shukla and published by Springer Nature. This book was released on 2021-05-15 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: div="" This book covers different aspects related to utilization of alcohol fuels in internal combustion (IC) engines with a focus on combustion, performance and emission investigations. The focal point of this book is to present engine combustion, performance and emission characteristics of IC engines fueled by alcohol blended fuels such as methanol, ethanol and butanol. The contents also highlight the importance of alcohol fuel for reducing emission levels. Possibility of alcohol fuels for marine applications has also been discussed. This book is a useful guide for researchers, academics and scientists. ^

Download or read book The Influence of N butanol Blending on the Ignition Delay Times of Gasoline and Its Surrogate at High Pressures 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 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 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 Experimental Evaluation of Water containing Isopropanol n butanol ethanol and Gasoline Blend as a Fuel Candidate in Spark ignition Engine written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Diesel Fuel Oils written by and published by . This book was released on 1960 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Investigation Into the Auto Ignition and Sooting Properties of 2 Methyl 3 buten 2 ol for Replacing Ethanol and Isobutanol as a Gasoline Fuel Component written by Stephen Sakai (Ph.D.) and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this work was to investigate the relative particulate formation and knock-resistance of equal oxygen weight blends of ethanol, isobutanol, and 2-methyl-3-buten-2-ol with gasoline. Combustion experiments were conducted in a spark-ignition engine operated in premixed prevaporized and direct-injection modes to examine knocking behavior and particulate formation. Spray visualization experiments were performed to characterize the effects of alcohol addition on spray behavior. For knock-limited combustion experiments, increasing alcohol content generally reduced knock. Overall, 2-methyl-3-buten-2-ol showed significantly improved knock-resistance compared to the other two alcohols. The results between fuel blends were similar for both combustion modes. Direct-injection operation yielded significant increases in knock resistance for higher-level blends. The results of these studies indicate that the order of knock-resistance of these three alcohols, for both operating modes, is isobutanol

Download or read book Characterization and Properties of Petroleum Fractions written by M. R. Riazi and published by ASTM International. This book was released on 2005 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: The last three chapters of this book deal with application of methods presented in previous chapters to estimate various thermodynamic, physical, and transport properties of petroleum fractions. In this chapter, various methods for prediction of physical and thermodynamic properties of pure hydrocarbons and their mixtures, petroleum fractions, crude oils, natural gases, and reservoir fluids are presented. As it was discussed in Chapters 5 and 6, properties of gases may be estimated more accurately than properties of liquids. Theoretical methods of Chapters 5 and 6 for estimation of thermophysical properties generally can be applied to both liquids and gases; however, more accurate properties can be predicted through empirical correlations particularly developed for liquids. When these correlations are developed with some theoretical basis, they are more accurate and have wider range of applications. In this chapter some of these semitheoretical correlations are presented. Methods presented in Chapters 5 and 6 can be used to estimate properties such as density, enthalpy, heat capacity, heat of vaporization, and vapor pressure. Characterization methods of Chapters 2-4 are used to determine the input parameters needed for various predictive methods. One important part of this chapter is prediction of vapor pressure that is needed for vapor-liquid equilibrium calculations of Chapter 9.