Download or read book The Effect of Ethanol Addition to Gasoline on Low and Intermediate Temperature Heat Release Under Boosted Conditions in Kinetically Controlled Engines written by David Malcolm Vuilleumier and published by . This book was released on 2016 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract The Effect of Ethanol Addition to Gasoline on Low- and Intermediate-Temperature Heat Release under Boosted Conditions in Kinetically Controlled Engines by David Malcolm Vuilleumier Doctor of Philosophy in Mechanical Engineering University of California, Berkeley Professor Jyh-Yuan Chen, Chair The detailed study of chemical kinetics in engines has become required to further advance engine efficiency while simultaneously lowering engine emissions. This push for higher efficiency engines is not caused by a lack of oil, but by efforts to reduce anthropogenic carbon dioxide emissions, that cause global warming. To operate in more efficient manners while reducing traditional pollutant emissions, modern internal combustion piston engines are forced to operate in regimes in which combustion is no longer fully transport limited, and instead is at least partially governed by chemical kinetics of combusting mixtures. Kinetically-controlled combustion allows the operation of piston engines at high compression ratios, with partially-premixed dilute charges; these operating conditions simultaneously provide high thermodynamic efficiency and low pollutant formation. The investigations presented in this dissertation study the effect of ethanol addition on the low-temperature chemistry of gasoline type fuels in engines. These investigations are carried out both in a simplified, fundamental engine experiment, named Homogeneous Charge Compression Ignition, as well as in more applied engine systems, named Gasoline Compression Ignition engines and Partial Fuel Stratification engines. These experimental investigations, and the accompanying modeling work, show that ethanol is an effective scavenger of radicals at low temperatures, and this inhibits the low temperature pathways of gasoline oxidation. Further, the investigations measure the sensitivity of gasoline auto-ignition to system pressure at conditions that are relevant to modern engines. It is shown that at pressures above 40 bar and temperatures below 850 Kelvin, gasoline begins to exhibit Low-Temperature Heat Release. However, the addition of 20% ethanol raises the pressure requirement to 60 bar, while the temperature requirement remains unchanged. These findings have major implications for a range of modern engines. Low-Temperature Heat Release significantly enhances the auto-ignition process, which limits the conditions under which advanced combustion strategies may operate. As these advanced combustion strategies are required to meet emissions and fuel-economy regulations, the findings of this dissertation may benefit and be incorporated into future engine design toolkits, such as detailed chemical kinetic mechanisms.

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 Advanced Combustion Techniques and Engine Technologies for the Automotive Sector written by Akhilendra Pratap Singh and published by Springer Nature. This book was released on 2019-10-10 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the recent advances in combustion strategies and engine technologies, with specific reference to the automotive sector. Chapters discuss the advanced combustion technologies, such as gasoline direct ignition (GDI), spark assisted compression ignition (SACI), gasoline compression ignition (GCI), etc., which are the future of the automotive sector. Emphasis is given to technologies which have the potential for utilization of alternative fuels as well as emission reduction. One special section includes a few chapters for methanol utilization in two-wheelers and four wheelers. The book will serve as a valuable resource for academic researchers and professional automotive engineers alike.

Download or read book Characteristics and Control of Low Temperature Combustion Engines written by Rakesh Kumar Maurya and published by Springer. This book was released on 2017-11-03 with total page 553 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with novel advanced engine combustion technologies having potential of high fuel conversion efficiency along with ultralow NOx and particulate matter (PM) emissions. It offers insight into advanced combustion modes for efficient utilization of gasoline like fuels. Fundamentals of various advanced low temperature combustion (LTC) systems such as HCCI, PCCI, PPC and RCCI engines and their fuel quality requirements are also discussed. Detailed performance, combustion and emissions characteristics of futuristic engine technologies such as PPC and RCCI employing conventional as well as alternative fuels are analyzed and discussed. Special emphasis is placed on soot particle number emission characterization, high load limiting constraints, and fuel effects on combustion characteristics in LTC engines. For closed loop combustion control of LTC engines, sensors, actuators and control strategies are also discussed. The book should prove useful to a broad audience, including graduate students, researchers, and professionals Offers novel technologies for improved and efficient utilization of gasoline like fuels; Deals with most advanced and futuristic engine combustion modes such as PPC and RCCI; Comprehensible presentation of the performance, combustion and emissions characteristics of low temperature combustion (LTC) engines; Deals with closed loop combustion control of advanced LTC engines; State-of-the-art technology book that concisely summarizes the recent advancements in LTC technology. .

Download or read book Assessing the Effects of Ethanol Addition on Particulate Matter Emissions in GDI Engines written by Yihao Zhang (S. M.) and published by . This book was released on 2018 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous research on the effects of ethanol addition on particulate matter (PM) emissions in GDI engines show diverse results. In this thesis, an overview on three major aspects, PM formation, effects of engine operating conditions, and ethanol effects, unveils the large number of factors that can simultaneously affect PM emissions from gasoline-ethanol blends in GDI engines, partially explaining the reasons for the diverse results from previous research. A further experimental work was conducted to assess three potential ethanol effects, displacement effect, evaporative cooling effect, and oxygen content effect. The displacement effect is based on PM Index (PMI) in the literature. Ethanol has very low PMI and thus very low propensity to form PM. Therefore, the addition of ethanol replaces the high-PMI components in the gasoline, lowering PM emissions. Although the PMI value incorporates species reactivity and volatility, it does not take latent heat of vaporization (HOV) into account. The high HOV of ethanol suppresses the fuel evaporation and potentially causes more liquid fuel films, which serve as sources for PM emissions. This evaporative cooling effect was assessed along with the oxygen content effect, a widely used effect in the literature to explain why ethanol lowers PM emissions. Through the method of control variables, the displacement effect and oxygen content effect were separated out and could be assessed individually. The existence of the displacement effect was confirmed. It was also found that the oxygen content effect was negligible, while the evaporative cooling effect changed PN emission significantly. The extent of the evaporative cooling effect depended on operating conditions, such as fuel injection timing, engine coolant temperature, and load.

Download or read book SI Combustion written by and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ethanol Fuel Modification for Highway Vehicle Use written by and published by . This book was released on 1980 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Low temperature Combustion and Autoignition written by M.J. Pilling and published by Elsevier. This book was released on 1997-11-27 with total page 823 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion has played a central role in the development of our civilization which it maintains today as its predominant source of energy. The aim of this book is to provide an understanding of both fundamental and applied aspects of low-temperature combustion chemistry and autoignition. The topic is rooted in classical observational science and has grown, through an increasing understanding of the linkage of the phenomenology to coupled chemical reactions, to quite profound advances in the chemical kinetics of both complex and elementary reactions. The driving force has been both the intrinsic interest of an old and intriguing phenomenon and the centrality of its applications to our economic prosperity. The volume provides a coherent view of the subject while, at the same time, each chapter is self-contained.

Download or read book Introduction to Modeling and Control of Internal Combustion Engine Systems written by Lino Guzzella and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: Internal combustion engines still have a potential for substantial improvements, particularly with regard to fuel efficiency and environmental compatibility. These goals can be achieved with help of control systems. Modeling and Control of Internal Combustion Engines (ICE) addresses these issues by offering an introduction to cost-effective model-based control system design for ICE. The primary emphasis is put on the ICE and its auxiliary devices. Mathematical models for these processes are developed in the text and selected feedforward and feedback control problems are discussed. The appendix contains a summary of the most important controller analysis and design methods, and a case study that analyzes a simplified idle-speed control problem. The book is written for students interested in the design of classical and novel ICE control systems.

Download or read book Advances in Internal Combustion Engine Research written by Dhananjay Kumar Srivastava and published by Springer. This book was released on 2017-11-29 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses all aspects of advanced engine technologies, and describes the role of alternative fuels and solution-based modeling studies in meeting the increasingly higher standards of the automotive industry. By promoting research into more efficient and environment-friendly combustion technologies, it helps enable researchers to develop higher-power engines with lower fuel consumption, emissions, and noise levels. Over the course of 12 chapters, it covers research in areas such as homogeneous charge compression ignition (HCCI) combustion and control strategies, the use of alternative fuels and additives in combination with new combustion technology and novel approaches to recover the pumping loss in the spark ignition engine. The book will serve as a valuable resource for academic researchers and professional automotive engineers alike.

Download or read book Coefficients for Calculating Thermodynamic and Transport Properties of Individual Species written by Bonnie J. McBride and published by . This book was released on 1993 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Review of the 21st Century Truck Partnership written by National Research Council and published by National Academies Press. This book was released on 2008-10-19 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 21st Century Truck Partnership (21CTP), a cooperative research and development partnership formed by four federal agencies with 15 industrial partners, was launched in the year 2000 with high hopes that it would dramatically advance the technologies used in trucks and buses, yielding a cleaner, safer, more efficient generation of vehicles. Review of the 21st Century Truck Partnership critically examines and comments on the overall adequacy and balance of the 21CTP. The book reviews how well the program has accomplished its goals, evaluates progress in the program, and makes recommendations to improve the likelihood of the Partnership meeting its goals. Key recommendations of the book include that the 21CTP should be continued, but the future program should be revised and better balanced. A clearer goal setting strategy should be developed, and the goals should be clearly stated in measurable engineering terms and reviewed periodically so as to be based on the available funds.

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 Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy Duty Vehicles written by National Research Council and published by National Academies Press. This book was released on 2010-07-30 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: Technologies and Approaches to Reducing the Fuel Consumption of Medium- and Heavy-Duty Vehicles evaluates various technologies and methods that could improve the fuel economy of medium- and heavy-duty vehicles, such as tractor-trailers, transit buses, and work trucks. The book also recommends approaches that federal agencies could use to regulate these vehicles' fuel consumption. Currently there are no fuel consumption standards for such vehicles, which account for about 26 percent of the transportation fuel used in the U.S. The miles-per-gallon measure used to regulate the fuel economy of passenger cars. is not appropriate for medium- and heavy-duty vehicles, which are designed above all to carry loads efficiently. Instead, any regulation of medium- and heavy-duty vehicles should use a metric that reflects the efficiency with which a vehicle moves goods or passengers, such as gallons per ton-mile, a unit that reflects the amount of fuel a vehicle would use to carry a ton of goods one mile. This is called load-specific fuel consumption (LSFC). The book estimates the improvements that various technologies could achieve over the next decade in seven vehicle types. For example, using advanced diesel engines in tractor-trailers could lower their fuel consumption by up to 20 percent by 2020, and improved aerodynamics could yield an 11 percent reduction. Hybrid powertrains could lower the fuel consumption of vehicles that stop frequently, such as garbage trucks and transit buses, by as much 35 percent in the same time frame.

Download or read book Vehicle Propulsion Systems written by Lino Guzzella and published by Springer Science & Business Media. This book was released on 2007-09-21 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors of this text have written a comprehensive introduction to the modeling and optimization problems encountered when designing new propulsion systems for passenger cars. It is intended for persons interested in the analysis and optimization of vehicle propulsion systems. Its focus is on the control-oriented mathematical description of the physical processes and on the model-based optimization of the system structure and of the supervisory control algorithms.

Download or read book MILD Combustion Modelling Challenges Experimental Configurations and Diagnostic Tools written by Alessandro Parente and published by Frontiers Media SA. This book was released on 2021-11-26 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Direct Injection for Dual Fuel Stratification DDFS written by and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low temperature combustion (LTC) strategies can achieve high thermal efficiency with low engine-out NOx and soot emissions. However, controlling the timing and rate of heat release under LTC conditions in a consistent manner has proven to be difficult, and emissions of CO and unburned hydrocarbons (HC) are high. Several fueling strategies have been developed to create stratification of equivalence ratio and ignition delay such that heat release is retarded and lengthened, but these strategies typically result in a trade-off between efficiency and noise, a narrow operating range, or impractical boundary conditions, and the issue of high CO and HC emissions remains. In this research, a new strategy is proposed in which two fuels with different autoignition characteristics are introduced to the cylinder via multiple direct injections, allowing for greater control and range of reactivity and equivalence ratio distribution, as well as the possibility of mixed combustion modes. A series of experiments detail the development of the fueling strategy, an exploration of the parameters contributing to noise and emissions, a pathway to practical high-load operation, and a comparison to existing LTC strategies. By direct-injecting two fuels, it is possible to gain a new level of control over the shape and stability of the heat release event, along with the ability to combine and exploit the practical benefits of existing combustion strategies in a manner that was previously impossible.