Download or read book Development of Surrogates for Aviation Jet Fuels written by Seyed Ali Nasseri and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a Chemical Surrogate for JP 8aviation Fuel Using a Pressurized Flow Reactor written by Alessandro Agosta and published by . This book was released on 2002 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Fuel Structure Effects on Surrogate Alternative Jet Fuel Emission written by Giacomo Flora and published by . This book was released on 2015 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: The emergence of alternative jet fuels has opened new challenges for the selection of practical alternatives that minimize the emissions and are suitable for existing gas turbine engines. Alternative jet fuels are in the early stages of development, and little fundamental emissions data are currently available. An accurate knowledge of their combustion behavior is highly important for a proper fuel selection based on emissions.This dissertation work investigated the oxidation of different alternative fuel surrogates composed of binary mixtures in order to correlate fuel composition with emissions. The proposed surrogate mixtures included n-dodecane/n-heptane (47.5/52.5 by liq. vol.), n-dodecane/iso-octane (47.9/52.1 by liq, vol.), n-dodecane/methylcyclohexane (49/51 by liq. vol.) and n-dodecane/m-xylene (75/25 by liq. vol.) mixtures. Experiments were carried out at the UDRI heated shock tube facility, and covered a pre-ignition temperature range of 950--1550 K at a pre-ignition pressure of ~16 atm, an equivalence ratio of 3, an argon concentration of 93% (by mol), and under homogeneous gas-phase conditions. Experimental data were modeled using the 2014 SERDP mechanism for jet fuel surrogates (525 species and 3199 reactions). Similar ignition delay times were measured for the tested surrogate blends, confirming previous observations regarding the controlling role of normal alkanes during the induction period. The experimental observation was also compared with modeling results reporting reasonably good agreements. A kinetic analysis of the SERDP 2014 mechanism was also performed, highlighting the major chemical pathways relevant to the pre-ignition chemistry, especially the role of the hydroperoxyl radical at the low temperatures. A wide speciation of combustion products was also carried out under the test conditions. All the aliphatic blends reported similar emissions, whereas the presence of m-xylene produced lower emissions than the aliphatic surrogate blends at lower temperatures. For certain species (light gases) this experimental observation was also supported by the kinetic mechanism predictions. However, aromatic species formed from combustion of n-dodecane/m-xylene surrogate blend were always overestimated by the model and in poor agreement with experimental observations. The results also confirmed the role of acetylene as assisting growth of large PAHs and formation of soot.
Download or read book Laminar Flame Speed of Jet Fuel Surrogates and Second Generation Biojet Fuel Blends written by Jeffrey Munzar and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "An understanding of the fundamental combustion properties of alternative fuels is essential for their adoption as replacements for non-renewable sources. In the aviation industry, a promising candidate is hydrotreated renewable jet fuel (HRJF). HRJF can be synthesized in a sustainable and economically viable manner from long chain fatty-acid methyl esters found in jatropha and camelina seed, and the laboratory-scale characterization of the combustion properties of HRJF is an active area of research. Such research is motivated, in part, by the chemical complexity of biojet fuels which are composed of hundreds of hydrocarbon species, similar to conventional aviation grade fuels. The laminar flame speed has been identified as an important combustion parameter for many combustion applications, and is especially relevant to the aviation community. The laminar flame speed is also an important parameter in the validation of chemical kinetic mechanisms, as it is representative of the chemical reactivity of the fuel. In this study, laminar, atmospheric pressure, premixed stagnation flames were used to determine the laminar flame speed of HRJF blended in varying ratios with Jet A-1 aviation fuel, requiring a combination of experimental and numerical methods. Jet A-1 was also studied to allow for comparative benchmarking of the biojet blends. Experiments were carried out in a jet-wall stagnation flame geometry at a pre-heated temperature of 400 K. Centerline velocity profiles were obtained using particle image velocimetry, from which the strained reference flame speeds were determined. Simulations of each experiment were carried out using the CHEMKIN-PRO software package together with a detailed chemical kinetic mechanism, with the specification of necessary boundary conditions taken entirely from experimental measurements. A direct comparison method was used to infer the true laminar flame speed from the experimental and numerical strained reference flame speeds. In order to model the chemical kinetics of Jet A-1 and the biojet blends, it was necessary to identify a surrogate blend that emulates the reactivity of the biojet fuels, while consisting of a much smaller number of pure compounds. Published data shows significant discrepancies for many jet fuel surrogate components, motivating their inclusion in this study. Thus, laminar flame speeds were also obtained for three candidate jet fuel surrogate components: n-decane, methylcyclohexane and toluene, which are representative of the alkane, cycloalkane and aromatic components of conventional aviation fuel, respectively. Results for the pure surrogate components were used to generate a suitable surrogate blend for the biojet blends. The results form this work resolve conflicting laminar flame speed data for the surrogate components, which is essential for the further development of chemical kinetic mechanisms and contributes to the surrogate modelling of jet fuel combustion. The laminar flame speeds of the biojet blends are compared to the Jet A-1 benchmark over a wide range of equivalence ratios. The biojet blends are found to behave similarly to Jet A-1 for low to moderate levels of blending, but show a marked disagreement otherwise." --
Download or read book The Development and Application of Surrogate Blends in Simulating the Combustion Performance of Distillate Aviation Fuels written by Craig Pierce Wood and published by . This book was released on 1989 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flame Propagation of Jet A 1 Fuel and Its Surrogates written by Bradley Denman and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The laminar flame speed is an essential flame parameter for both chemical kinetic mechanism validation and turbulent combustion studies. Kerosene-derived jet fuel flame speeds, however, are largely unknown and due to complex composition of the fuels themselves they cannot be modelled numerically. To overcome this limitation surrogate fuels and blends are used to reproduce the same flame speed of amore complex mixture. To accomplish this for aviation fuel, a database is created of four potential jet fuel surrogate components for laminar flame speed. The neat hydrocarbon surrogates investigated are n-dodecane and n-decane, methylcyclohex-ane, and toluene, which represent the alkane, cycloalkane, and aromatic components of conventional aviation fuel, respectively. Several blends of these surrogate fuels are tested experimentally and numerically to validate the effect of blend composition on flame speed. The database is then used to develop a blend to match the flame speeds of a commercial aviation fuel, Jet A-1. Unlike previous investigations of flame propagation, in this study, numerical simulations are directly compared to velocity profile measurements in laminar stagnation flames to extrapolate to a condition of zero flame stretch. Numerical simulations of each experiment are obtained using the CHEMKIN-PRO software package and the JetSurF 2.0 mechanism with accurate specification of all necessary boundary conditions from experimental measurements. The advantage of this technique is that the extrapolation to the unstretched condition is independent of the how well the mechanism predicts reactivity. Therefore, JetSurF 2.0 was simultaneously validated for each of the surrogate fuels and blends in a previously unused manner. The mechanism showed relatively good agreement for the n-alkane and cycloalkane fuels for which it was optimized for, while consistently under predicted the reactivity of toluene. The compiled database of jet fuel surrogate components allowed for five different potential surrogate mixtures to be developed. Experimental results of these blends suggest that although jet fuel is a very complex mixture a simple surrogate mixture consisting of 73% n-decane and 27% toluene byvolume appropriately matches the flame speed of Jet A-1. Numerical results using JetSurF 2.0 suggest that a 63% n-decane and 37% toluene by volume blend is the most appropriate surrogate and this was used to extrapolate the experimental JetA-1 results and determine its laminar flame speed." --
Download or read book Biojet Fuel in Aviation Applications written by Cheng Tung Chong and published by Elsevier. This book was released on 2021-06-27 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biojet fuels have the potential to make an important contribution towards decarbonising the aviation sector. Biojet Fuel in Aviation Applications: Production, Usage and Impact of Biofuels covers all aspects of this sustainable aviation fuel including aviation biofuel public policies, production technologies, physico-chemical properties, combustion performances, techno-economics of sustainable fuel production, sustainability and energywater-food (EWF) nexus. This must-have book also charts the current state of the industry by discussing the relevant industry players who are currently producing alternative aviation fuels and flight tests, while also providing a glimpse of the future of the industry. This comprehensive book is written for undergraduate students, postgraduate students, researchers, engineers and policy makers wanting to build up knowledge in the specific area of biojet fuel or the broader fields of sustainable energy and aeronautics. Reviews major aviation and biojet fuel policies, legislations, initiatives and roadmaps around the world Features existing and emerging biojet fuel production pathways from various feedstocks Highlights the key properties of biojet fuels that ensures inter-operability with conventional jet aviation fuel Discusses the economic aspects of the biojet fuel industry and the barriers preventing its commercialisation Examines the sustainability of biojet fuel from a life cycle assessment, energy balance and EWF nexus point of views
Download or read book Formulation and Some Applications of Jet Fuel Surrogates written by Shihong Yan and published by . This book was released on 2005 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study on the Sooting Tendency of Jet Fuel Surrogates Using the Threshold Soot Index written by Amy Mensch and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Engine Spray and Combustion Processes written by Gunnar Stiesch and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: The utilization of mathematical models to numerically describe the performance of internal combustion engines is of great significance in the development of new and improved engines. Today, such simulation models can already be viewed as standard tools, and their importance is likely to increase further as available com puter power is expected to increase and the predictive quality of the models is constantly enhanced. This book describes and discusses the most widely used mathematical models for in-cylinder spray and combustion processes, which are the most important subprocesses affecting engine fuel consumption and pollutant emissions. The relevant thermodynamic, fluid dynamic and chemical principles are summarized, and then the application of these principles to the in-cylinder processes is ex plained. Different modeling approaches for the each subprocesses are compared and discussed with respect to the governing model assumptions and simplifica tions. Conclusions are drawn as to which model approach is appropriate for a specific type of problem in the development process of an engine. Hence, this book may serve both as a graduate level textbook for combustion engineering stu dents and as a reference for professionals employed in the field of combustion en gine modeling. The research necessary for this book was carried out during my employment as a postdoctoral scientist at the Institute of Technical Combustion (ITV) at the Uni versity of Hannover, Germany and at the Engine Research Center (ERC) at the University of Wisconsin-Madison, USA.
Download or read book Toxicologic Assessment of Jet Propulsion Fuel 8 written by National Research Council and published by National Academies Press. This book was released on 2003-02-14 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report provides a critical review of toxicologic, epidemiologic, and other relevant data on jet-propulsion fuel 8, a type of fuel in wide use by the U.S. Department of Defense (DOD), and an evaluation of the scientific basis of DOD's interim permissible exposure level of 350 mg/m3
Download or read book Federal Alternative Jet Fuels Research and Development Strategy written by National Science National Science and Technology Council and published by Createspace Independent Publishing Platform. This book was released on 2017-01-09 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: The U.S. civil and military aviation community has historically relied upon energy-dense liquid jet fuel that is derived from petroleum, which is subject to volatile pricing and uncertain supply and harmful to the environment. More recently developed jet fuel alternatives derived from nonpetroleum feedstock can help address those issues and other U.S. energy-related challenges, making development of alternative energy fuels (AJFs) of increased interest in the realm of aviation. Effective Federal research and development can enable AJF development by reducing the costs of producing fuel, facilitating effective evaluation and approval of promising fuel pathways, ensuring that environmental and social benefits accrue from the use of these fuels, reducing technical uncertainty, and promoting private sector investment in production.
Download or read book Surrogate Modeling of Alternative Jet Fuels for Study of Autoignition Characteristics written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Alternative Jet Fuels and Effect of Residual Oxygenated Functions Groups on Their Properties written by Anamaria Paiva Pinheiro Pires and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Detailed and Simplified Chemical Kinetics of Aviation Fuels and Surrogates written by Valentini Markaki and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistries of aviation fuels are invariably complex due to largehydrocarbon molecules. There are also large variations for a given fuel type. Furthermore, flow timescales encountered in high performance propulsion devicesincreasingly lead to difficulties associated with kinetically controlled or influencedphenomena such as flame stability, extinction and re-light. Current indications alsosuggest that fuel sources will become significantly more diverse in the future andmay, for example, encompass Fischer-Tropsch and/or bio-derived components. Thecombustion properties of such fuels can vary significantly from those in current useand this work outlines a route towards surrogate fuel mechanisms of sufficientaccuracy and generality to support the development of practical devices. A reaction class based route to the derivation of detailed chemical kineticmechanisms for alkyl-substituted aromatics is outlined and applied to thecyclopentadiene/indene, benzene/naphthalene, toluene/1-methyl naphthalenesystems. Work has also been extended to the n-propyl benzene system as well. These reaction classes were applied to model the oxidation of the above fuels withencouraging results. Important reaction channels during oxidation were identifiedand specifically, the methyl groups on aromatic rings have been identified asimportant in the context of radical scavenging. Furthermore, 1-methyl naphthalenemay also be used to modulate sooting tendencies in aviation and Diesel surrogates. Results obtained from chemical kinetic modelling of cyclopentadiene, toluene, npropylbenzene, naphthalene and 1-methyl naphthalene oxidation in shock tubes, jet-stirred and plug-flow reactors at various sets of representative stoichiometriesand temperatures are reported.
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.
