Download or read book Fast Reactions in Energetic Materials written by Alexander S. Shteinberg and published by Springer Science & Business Media. This book was released on 2008-09-26 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern energetic materials include explosives, blasting powders, pyrotechnic m- tures and rocket propellants [1, 2]. The study of high-temperature decomposition of condensed phases of propellants and their components (liquid, solid and hybrid) is currently of special importance for the development of space-system engineering [3, 4]. To better understand the burning mechanisms (stationary, nonstationary, - steady) of composite solid propellants and their components, information about the macrokinetics of their high-temperature decomposition is required [5]. To be able to evaluate the ignition parameters and conditions of safe handling of heat-affected explosives, one needs to know the kinetic constants of their high-temperature - composition. The development of new composite solid propellants characterized by high performance characteristics (high burning rates, high thermal stability, stability to intrachamber perturbations, and other aspects) is not possible without quanti- tive data on the high-temperature decomposition of composite solid propellants and their components [6]. The same reasons have resulted in signi?cant theoretical and practical interest in the high-temperature decomposition of components of hybrid propellants. It is known that hybrid propellants have not been used very widely due to the low bu- ing (pyrolysis) rates of the polymer blocks in the combustion chambers of hybrid rocket engines. To increase the burning rates it is necessary to obtain information about their relationships to the corresponding kinetic and thermophysical prop- ties of the fuels.
Download or read book Fast Reactions in Energetic Systems written by Christos Capellos and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 747 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the formal lectures and contributed papers given at the NATO Advanced Study Institute on Fast Reactions in Energetic Systems, which took place in Preveza, Greece, during the period 6-19 July 1980. The material describes experimental observations and the more advanced theoretical aspects of certain types of fast reactions and energy or charge transfer processes which are usually complete 6 12 in periods of 10- - 10- seconds. Furthermore, it discusses the role of macroscopic and molecular processes in the ignition, combustion, deflagration, and detonation of solid, liquid, and gaseous chemical systems. Various papers deal with the ability of molecules to absorb and transmit the different forms of energy provided by shock, light, thermal, or electron pulses, and to contribute to the propagation of reactions under high temperatures and pressures. The role of energy pumped or transferred to electronic or vibrational states is discussed in terms of excitation, ionization, bond scission, and the formation of free radicals. The dynamics and reactivity of ionic species, electronically and vibrationally excited states, and free radicals are described for various gaseous, liquid, and solid systems. The proceedings include presentations of theoretical and experimental techniques to describe and observe the phenomena.
Download or read book Energetic Materials written by and published by Elsevier. This book was released on 2003-11-21 with total page 475 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides an overview of current research and recent advances in the area of energetic materials, focusing on explosives and propellants. The contents and format reflect the fact that theory, experiment and computation are closely linked in this field. The challenge of developing energetic materials that are less sensitive to accidental stimuli continues to be of critical importance. This volume opens with discussions of some determinants of sensitivity and its correlations with various molecular and crystal properties. The next several chapters deal in considerable detail with different aspects and mechanisms of the initiation of detonation, and its quantitative description. The second half of this volume focuses upon combustion. Extensive studies model ignition and combustion, with applications to different propellants. The final chapter is an exhaustive computational treatment of the mechanism and kinetics of combustion initiation reactions of ammonium perchlorate. Overall, this volume illustrates the progress that has been made in the field of energetic materials and some of the areas of current activity. It also indicates the challenges involved in characterizing and understanding the properties and behaviour of these compounds. The work is a unique state-of-the-art treatment of the subject, written by pre-eminent researchers in the field. - Overall emphasis is on theory and computation, presented in the context of relevant experimental work - Presents a unique state-of-the-art treatment of the subject - Contributors are preeminent researchers in the field
Download or read book Overviews Of Recent Research On Energetic Materials written by Donald L Thompson and published by World Scientific. This book was released on 2005-08-02 with total page 531 pages. Available in PDF, EPUB and Kindle. Book excerpt: Few books cover experimental and theoretical methods to characterize decomposition, combustion and detonation of energetic materials. This volume, by internationally known and major contributors to the field, is unique because it summarizes the most important recent work, what we know with confidence, and what main areas remain to be investigated. Most chapters comprise summaries of work spanning decades and contain expert commentary available nowhere else. Although energetic materials are its focus, this book provides a guide to modern methods for investigations of condensed and gas-phase reactions. Although these energetic reactions are complex and difficult to study, the work discussed here provides readers with a substantial understanding of the behavior of materials now in use, and a predictive capability for the development of new materials based on target properties.
Download or read book Energetic Materials written by and published by Elsevier. This book was released on 2003-11-25 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides an overview of current research and recent advances in the area of energetic materials, focusing on decomposition, crystal and molecular properties. The contents and format reflect the fact that theory, experiment and computation are closely linked in this field. Since chemical decomposition is of fundamental importance in energetic performance, this volume begins with a survey of the decomposition processes of a variety of energetic compounds. This is followed by detailed studies of certain compounds and specific mechanisms, such as nitro/aci-nitro tautomerism. Chapter 6 covers the transition from decomposition to crystal properties, with molecular dynamics being the primary analytical tool. The next several chapters deal with different aspects of the crystalline state, again moving from the general to particular. There is also a discussion of methods for computing gas, liquid and solid phase heats of formation. Finally, the last portion of this volume looks at the potential of high-nitrogen molecules as energetic systems; this has been of considerable interest in recent years.Overall, this volume illustrates the progress that has been made in the field of energetic materials and some of the areas of current activity. It also indicates the challenges involved in characterizing and understanding the properties and behaviour of these compounds. The work is a unique state-of-the-art treatment of the subject, written by pre-eminent researchers in the field. - Overall emphasis is on theory and computation, presented in the context of relevant experimental work- Presents a unique state-of-the-art treatment of the subject- Contributors are preeminent researchers in the field
Download or read book Explosive Chemistry written by and published by . This book was released on 2003 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the brief instant of a high-explosive detonation, the shock wave produces a pressure 500,000 times that of the Earth's atmosphere, the detonation wave travels as fast as 10 kilometers per second, and internal temperatures soar up to 5,500 Kelvin. As the shock propagates through the energetic material, the rapid heating coupled with compression that results in almost 30% volume reduction, initiate complex chemical reactions. A dense, highly reactive supercritical fluid is established behind the propagating detonation front. Energy release from the exothermic chemical reactions serve in turn to drive and sustain the detonation process until complete reactivity is reached. Several experimental results suggest the existence of strong correlations between the applied mechanical stress and shocks, the local heterogeneity and defects (dislocations, vacancies, cracks, impurities, etc.), and the onset of chemical reactions. The reaction chemistry of energetic materials at high pressure and temperature is, therefore, of considerable importance in understanding processes that these materials experience under impact and detonation conditions. Chemical decomposition models are critical ingredients in order to predict, among other things, the measured times to explosion and the conditions for ignition of hot spots, localized regions of highly concentrated energy associated with defects. To date, chemical kinetic rates of condense-phase energetic materials at detonation conditions are virtually non-existent, and basic questions such as: (a) which bond in a given energetic molecule breaks first, and (b) what type of chemical reactions (unimolecular versus bimolecular, etc.) that dominate early in the decomposition process, are still largely unknown.
Download or read book The Reactivity of Energetic Materials At Extreme Conditions written by and published by . This book was released on 2006 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energetic materials are unique for having a strong exothermic reactivity, which has made them desirable for both military and commercial applications. Energetic materials are commonly divided into high explosives, propellants, and pyrotechnics. We will focus on high explosive (HE) materials here, although there is a great deal of commonality between the classes of energetic materials. Although the history of HE materials is long, their condensed-phase properties are poorly understood. Understanding the condensed-phase properties of HE materials is important for determining stability and performance. Information regarding HE material properties (for example, the physical, chemical, and mechanical behaviors of the constituents in plastic-bonded explosive, or PBX, formulations) is necessary for efficiently building the next generation of explosives as the quest for more powerful energetic materials (in terms of energy per volume) moves forward. In modeling HE materials there is a need to better understand the physical, chemical, and mechanical behaviors from fundamental theoretical principles. Among the quantities of interest in plastic-bonded explosives (PBXs), for example, are thermodynamic stabilities, reaction kinetics, equilibrium transport coefficients, mechanical moduli, and interfacial properties between HE materials and the polymeric binders. These properties are needed (as functions of stress state and temperature) for the development of improved micro-mechanical models, which represent the composite at the level of grains and binder. Improved micro-mechanical models are needed to describe the responses of PBXs to dynamic stress or thermal loading, thus yielding information for use in developing continuum models. Detailed descriptions of the chemical reaction mechanisms of condensed energetic materials at high densities and temperatures are essential for understanding events that occur at the reactive front under combustion or detonation conditions. Under shock conditions, for example, energetic materials undergo rapid heating to a few thousand degrees and are subjected to a compression of hundreds of kilobars, resulting in almost 30% volume reduction. Complex chemical reactions are thus initiated, in turn releasing large amounts of energy to sustain the detonation process. Clearly, understanding of the various chemical events at these extreme conditions is essential in order to build predictive material models. Scientific investigations into the reactive process have been undertaken over the past two decades. However, the sub-[mu]s time scale of explosive reactions, in addition to the highly exothermic conditions of an explosion, make experimental investigation of the decomposition pathways difficult at best. More recently, new computational approaches to investigate condensed-phase reactivity in energetic materials have been developed. Here we focus on two different approaches to condensed-phase reaction modeling: chemical equilibrium methods and atomistic modeling of condensed-phase reactions. These are complementary approaches to understanding the chemical reactions of high explosives. Chemical equilibrium modeling uses a highly simplified thermodynamic picture of the reaction process, leading to a convenient and predictive model of detonation and other decomposition processes. Chemical equilibrium codes are often used in the design of new materials, both at the level of synthesis chemistry and formulation. Atomistic modeling is a rapidly emerging area. The doubling of computational power approximately every 18 months has made atomistic condensed-phase modeling more feasible. Atomistic calculations employ far fewer empirical parameters than chemical equilibrium calculations. Nevertheless, the atomistic modeling of chemical reactions requires an accurate global Born-Oppenheimer potential energy surface. Traditionally, such a surface is constructed by representing the potential energy surface with an analytical fit. This approach is only feasible for simple chemical reactions involving a small number of atoms. More recently, first principles molecular dynamics, where the electronic Schroedinger equation is solved numerically at each configuration in a molecular dynamics simulation, has become the method of choice for treating complicated chemical reactions.
Download or read book Probing the Dynamics of Ultra fast Condensed State Reactions in Energetic Materials written by Nicholas William Piekiel and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energetic Compounds written by Mohammad Hossein Keshavarz and published by Walter de Gruyter GmbH & Co KG. This book was released on 2020-05-05 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses methods for the assessment of energetic compounds through heat of detonation, detonation pressure, velocity and temperature, Gurney energy and power. The authors focus on the detonation pressure and detonation velocity of non-ideal aluminized energetic compounds. This 2nd Edition includes an updated and improved presentation of simple, reliable methods for the design, synthesis and development of novel energetic compounds.
Download or read book 1996 Gordon Research Conference on Energetic Materials written by and published by . This book was released on 1996 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Partial contents: Data collection in fast reactions; Energetic material synthesis; Initiation and detonation models; Energetic polymers; Non-ideal explosives; Experimental examination of detonation and combustion; Propellant combustion; Applied explosives chemistry.
Download or read book Molecular Modeling of the Sensitivities of Energetic Materials written by Didier Mathieu and published by Elsevier. This book was released on 2022-04-01 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular Modeling of the Sensitivities of Energetic Materials, Volume 22 introduces experimental aspects, explores the relationships between sensitivity, molecular structure and crystal structure, discusses insights from numerical simulations, and highlights applications of these approaches to the design of new materials. Providing practical guidelines for implementing predictive models and their application to the search for new compounds, this book is an authoritative guide to an exciting field of research that warrants a computer-aided approach for the investigation and design of safe and powerful explosives or propellants. Much recent effort has been put into modeling sensitivities, with most work focusing on impact sensitivity and leading to a lot of experimental data in this area. Models must therefore be developed to allow evaluation of significant properties from the structure of constitutive molecules. Highlights a range of approaches for computational simulation and the importance of combining them to accurately understand or estimate different parameters Provides an overview of experimental findings and knowledge in a quick and accessible format Presents guidelines to implement sensitivity models using open-source python-related software, thus supporting easy implementation of flexible models and allowing fast assessment of hypotheses
Download or read book Energetic Materials written by Institut Chemische Technologie and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Decomposition Combustion and Detonation Chemistry of Energetic Materials written by Thomas B. Brill and published by . This book was released on 1996 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energetic materials are distinguished from other materials primarily by the fact that rapid, exothermic reactions can be induced with the release of gaseous products. This complex phenomenon cuts across many boundaries of chemistry (synthesis, kinetics, thermodynamics, spectroscopy, quantum and molecular dynamics calculations, etc.) and engineering physics (shock and detonation waves, hydrodynamics, fracture and solid mechanics, defects, etc.). This volume offers the latest chemistry advancements in understanding the complex dynamic processes in these materials in the condensed phase. The focus is on fundamental research into the rates and pathways of rapid exothermic reactions, product specification, diagnostic methods, molecular processes of energy transfer, and molecular processes at extreme pressure and temperature. Many novel materials are discussed.
Download or read book Chemistry and Physics of Energetic Materials written by S.N. Bulusu and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book represents a collection of lectures presented at the NATO Advanced study Institute(ASI) on "Chemistry & Physics of the Molecular Processes in Energetic Materials", held at Hotel Torre Normanna, Altavilla Milicia, Sicily, Italy, September 3 to 15, 1989. The institute was attended by seventy participants including twenty lecturers, drawn from thirteen countries. The purpose of the institute was to review the major ad vances made in recent years in the theoretical and experi mental aspects of explosives and propellants. In accordance with the format of the NATO ASI, it was arranged to have a relatively small number of speakers to present in depth, re view type lectures emphasizing the basic research aspects of the subject, over a two week period. Most of the speakers gave two lectures, each in excess of one hour with addition al time for discussions. The scope of the meeting was limit ed to molecular and spectroscopic studies since the hydro dynamic aspects of detonation and various performance crite ria of energetic materials are often covered adequately in other international meetings. An attempt was made to have a coherent presentation of various theoretical, computational and spectroscopic approaches to help a better understanding of energetic materials from a molecular point of view. The progress already made in these areas is such that structure property (e. g.
Download or read book Flow Chemistry and the Synthesis of Energetic Materials written by and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Flow chemistry is seen as a disruptive innovation that expands chemistry's horizon and opens up new market possibilities. In addition to pharmaceutical applications, flow chemistry is expanding into organometallic chemistry, fine chemicals, polymers, peptides, nanomaterials, and energetic materials synthesis. In Chapter 2 of this report, we review the principles of flow chemistry, and highlight the potential benefits compared to performing reactions in batch mode. For example, flow reactors facilitate the fast dissipation of heat created during highly exothermic reactions, such as mixing of sulfuric-nitric acid, nitration reactions, or possible side reactions such as oxidation of nitro-aromatic compounds. Heat transfer rate in flow reactors can be magnitudes of orders faster than in a batch reactor and this prevents the hot-spot generation that can stimulate side reactions or runaway reactions to occur. Flow chemistry is also ideally suited for performing optimisation with design of experiments, which is a statistical approach used to optimise chemical processes and which allows a fuller investigation of parameter-space of a reaction, including cross-factor interactions. Reaction parameters such as temperature, pressure, flow rate, and amount of reagents can be controlled in a very precise and automated way via the system software, and it also straightforward to plan a sequence of experiments. Until now, the industrial production of energetic materials (i.e., explosives, propellants & pyrotechnics) has been dominated by traditional batch processing. Despite improvements in safety practices, accidents still occur during the production and processing of energetic materials for both the civilian and military market. The manufacturing of many high explosives is mainly done by applying nitration, as most are nitro compounds. Nitration is an exothermic chemical process to introduce a nitro group (-NO2) into an organic compound, and this step poses an elevated safety risk. However, the inherent advantages of flow chemistry are attracting interest in the energetics materials community, because of its potential to improve safety, reproducibility, and efficiency in the production of energetic materials. In Chapter 3 of this report, we review over 40 publications concerning the application of flow chemistry to synthesise energetic materials. The compounds concerned include nitro compounds, polynitrogen compounds, azides, styphnates, peroxides, peracids and energetic ionic liquids. Around three quarters of the publications were published during the last 10 years. Looking to the future, we can expect flow chemistry to play a central role in the trend towards increased automation in the selection, optimisation, and synthesis of novel compounds. In the area of energetic materials, a more widespread adoption of flow chemistry could - as part of a broad range of initiatives - contribute to enhanced safety in the production of explosives.
Download or read book Energetic Materials Detonation combustion written by Peter Politzer and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energetic Materials and Processes written by Zhenyu Du and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Special topic volume with invited peer reviewed papers only
