Download or read book Modeling Thermally Driven Energetic Response of High Explosives written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have improved our ability to model the response of energetic materials to thermal stimuli and the processes involved in the energetic response. Traditionally, the analyses of energetic materials have involved coupled thermal transport/chemical reaction codes. This provides only a reasonable estimate of the time and location of ensuing rapid reaction. To predict the violence of the reaction, the mechanical motion must be included in the wide range of time scales associated with the thermal hazard. The ALE3D code has been modified to assess the hazards associated with heating energetic materials in weapons by coupling to thermal transport model and chemistry models. We have developed an implicit time step option to efficiently and accurately compute the hours of heating to reaction of the energetic material. Since, on these longer time scales materials can be expected to have significant motion, it is even more important to provide high-order advection for all components, including the chemical species. We show two examples of coupled thermal/mechanical/chemical models of energetic materials in thermal environments.
Download or read book Modeling Thermally Driven Energetic Response of High Explosives in ALE3D written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have improved their ability to model the response of energetic materials to thermal stimuli and the processes involved in the energetic response. Traditionally, the analyses of energetic materials have involved coupled thermal transport/chemical reaction codes. This provides only a reasonable estimate of the time and location of ensuing rapid reaction. To predict the violence of the reaction, the mechanical motion must be included in the wide range of time scales associated with the thermal hazard. The ALE3D code has been modified to assess the hazards associated with heating energetic materials in weapons by coupling to thermal transport model and chemistry models. They have developed an implicit time step option to efficiently and accurately compute the hours of heating to reaction of the energetic material. Since, on these longer time scales materials can be expected to have significant motion, it is even more important to provide high-order advection for all components, including the chemical species. They show two examples of coupled thermal/mechanical/chemical models of energetic materials in thermal environments.
Download or read book A Model for High Explosive Cookoff written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have continued to improve our ability to model the response of energetic materials to thermal stimuli and the processes involved in the energetic response. Several new algorithms have been developed to increase the accuracy and fidelity of the modeling process. These include a level set driven multi-material deflagration model, a multi-temperature mixed material treatment, self-consistent thermal-hydro coupling, full implicit quasi-static hydrodynamics, ale slide surfaces and ale slide deletion. These capabilities have allowed us to improve our ability to model the cookoff process from the initial application of heat to the final metal expansion.
Download or read book Simulating the Thermal Response of High Explosives on Time Scales of Days to Microseconds written by M. A. McClelland and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present an overview of computational techniques for simulating the thermal cookoff of high explosives using a multi-physics hydrodynamics code, ALE3D. Recent improvements to the code have aided our computational capability in modeling the response of energetic materials systems exposed to extreme thermal environments, such as fires. We consider an idealized model process for a confined explosive involving the transition from slow heating to rapid deflagration in which the time scale changes from days to hundreds of microseconds. The heating stage involves thermal expansion and decomposition according to an Arrhenius kinetics model while a pressure-dependent burn model is employed during the explosive phase. We describe and demonstrate the numerical strategies employed to make the transition from slow to fast dynamics.
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 Emerging Energetic Materials Synthesis Physicochemical and Detonation Properties written by Dabir S. Viswanath and published by Springer. This book was released on 2018-01-02 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes science and technology of a new generation of high-energy andinsensitive explosives. The objective is to provide professionals with comprehensiveinformation on the synthesis and the physicochemical and detonation properties ofthe explosives. Potential technologies applicable for treatment of contaminated wastestreams from manufacturing facilities and environmental matrices are also be included.This book provides the reader an insight into the depth and breadth of theoreticaland empirical models and experimental techniques currently being developed in thefield of energetic materials. It presents the latest research by DoD engineers andscientists, and some of DoD’s academic and industrial researcher partners. The topicsexplored and the simulations developed or modified for the purposes of energetics mayfind application in other closely related fields, such as the pharmaceutical industry.One of the key features of the book is the treatment of wastewaters generated duringmanufacturing of these energetic materials.
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 143 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 Improving the Material Response for Slow Heat of Energetic Materials U written by and published by . This book was released on 2010 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of modern high explosive slow heat cookoff modeling is to understand the level of mechanical violence. This requires understanding the coupled thermal-mechanical-chemical system that such an environment creates. Recent advances have improved our ability to predict the time to event, and we have been making progress on predicting the mechanical response. By adding surface tension to the product gas pores in the high explosive, we have been able to reduce the current model's tendency to over-pressurize confinement vessels. We describe the model and demonstrate how it affects a LX-10 STEX experiment. Issues associated with current product gas equations of state are described and examined.
Download or read book Dynamic Behavior of Materials Volume 1 written by Vijay Chalivendra and published by Springer Science & Business Media. This book was released on 2012-09-26 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic Behavior of Materials, Volume 1: Proceedings of the 2012 Annual Conference on Experimental and Applied Mechanics represents one of seven volumes of technical papers presented at the Society for Experimental Mechanics SEM 12th International Congress & Exposition on Experimental and Applied Mechanics, held at Costa Mesa, California, June 11-14, 2012. The full set of proceedings also includes volumes on Challenges in Mechanics of Time -Dependent Materials and Processes in Conventional and Multifunctional Materials, Imaging Methods for Novel Materials and Challenging Applications, Experimental and Applied Mechanics, 2nd International Symposium on the Mechanics of Biological Systems and Materials 13th International Symposium on MEMS and Nanotechnology and, Composite Materials and the 1st International Symposium on Joining Technologies for Composites.
Download or read book Numerical Modeling of Explosives and Propellants Second Edition written by Charles L. Mader and published by CRC Press. This book was released on 1997-08-29 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Charles Mader, a leading scientist who conducted theoretical research at Los Alamos National Laboratory for more than 30 years, sets a new standard with this reference on numerical modeling of explosives and propellants. This book updates and expands the information presented in the author's landmark work, Numerical Modeling of Detonations, published in 1979 and still in use today. Numerical Modeling of Explosives and Propellants incorporates the considerable changes the personal computer has brought to numerical modeling since the first book was published, and includes new three-dimensional modeling techniques and new information on propellant performance and vulnerability. Both an introduction to the physics and chemistry of explosives and propellants and a guide to numerical modeling of detonation and reactive fluid dynamics, Numerical Modeling of Explosives and Propellants offers scientists and engineers a complete picture of the current state of explosive and propellant technology and numerical modeling. The book is richly illustrated with figures that support the concepts, and filled with tables for quick access to precise data. The accompanying CD-ROM contains computer codes that are the national standard by which modeling is evaluated. Dynamic material properties data files and animation files are also included. There is no other book available today that offers this vital information.
Download or read book Theory and Modeling of Thermal Reaction Propagation in Beam Initiated Explosives written by J. B Aviles (Jr) and published by . This book was released on 1993 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous work on the thermal initiation of energetic materials by particle beams concentrated on uniformly irradiated confined samples. The present report extends the work to situations where only a portion of the material has been irradiated. In some materials (e.g., TATB) only the irradiated region undergoes thermal initiation; in other materials a thermal initiation front has been observed (by thermocouple response) to propagate away from the irradiated region. The frontal speeds are of the order of centimeters per second to tens of centimeters per second. These slow speeds eliminate the possibility of pressure propagation or a deflagration to detonation transition (DDT). Modeling is based on the interference that at the thermal initiation temperature the material develops a greatly enhance thermal and gaseous diffusivity. This allows the exothermic energy released to propagate into the cold region and forestalls any explosive temperature rise. At a well defined positive R* (the explosion radius) thermal initiation propagation ceases and an explosive temperature rise takes place.
Download or read book Solid Propellant Chemistry Combustion and Motor Interior Ballistics 1999 written by Vigor Yang and published by AIAA. This book was released on 2000 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Integrated Experimental and Modeling Studies to Predict the Impact Response of Explosives and Propellants written by J. E. Reaugh and published by . This book was released on 2005 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding and predicting the impact response of explosives and propellants remains a challenging area in the energetic materials field. Efforts are underway at LLNL (and other laboratories) to apply modern diagnostic tools and computational analysis to move beyond the current level of imprecise approximations towards a predictive approach more closely based on fundamental understanding of the relevant mechanisms. In this paper we will discuss a set of underlying mechanisms that govern the impact response of explosives and propellants: (a) mechanical insult (impact) leading to material damage and/or direct ignition; (b) ignition leading to flame spreading; (c) combustion being driven by flame spreading, perhaps in damaged materials; (d) combustion causing further material damage; (e) combustion leading to pressure build-up or relief; (f) pressure changes driving the rates of combustion and flame spread; (g) pressure buildup leading to structural response and damage, which causes many of the physical hazards. We will briefly discuss our approach to modeling up these mechanistic steps using ALE 3D, the LLNL hydrodynamic code with fully coupled chemistry, heat flow, mass transfer, and slow mechanical motion as well as hydrodynamic processes. We will identify the necessary material properties needed for our models, and will discuss our experimental efforts to characterize these properties and the overall mechanistic steps, in order to develop and parameterize the models in ALE 3D and to develop a qualitative understanding of impact response.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1994 with total page 806 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book High Explosives Reaction Model and Its Application to Booster Performance written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Initiation of insensitive high explosives requires a boosting system using more sensitive and usually more energetic explosives. However, problems arise if the booster material is too energetic. The initiability of some insensitive but less energetic high explosives can be enhanced by lowering the density and decreasing the grain size or by adding a sensitive component; thus these explosives can be used as booster materials. This paper presents a unified initiation and detonation reaction model and then the simulation of the development of the detonation wave in a PBX-9502 main charge using three booster explosives: low-density superfine TATB, low-density ultrafine TATB, and X-0407. The last two are found to be acceptable for booster application. 12 refs., 5 figs.
Download or read book Dynamic Behavior of Materials Volume 1 written by Leslie E. Lamberson and published by Springer Nature. This book was released on 2019-11-20 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic Behavior of Materials, Volume 1 of the Proceedings of the 2019 SEM Annual Conference & Exposition on Experimental and Applied Mechanics, the first volume of six from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Experimental Mechanics, including papers on: Synchrotron Applications/Advanced Dynamic Imaging Quantitative Visualization of Dynamic Events Novel Experimental Techniques Dynamic Behavior of Geomaterials Dynamic Failure & Fragmentation Dynamic Response of Low Impedance Materials Hybrid Experimental/Computational Studies Shock and Blast Loading Advances in Material Modeling Industrial Applications
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt:
