Computational Simulation of Detonation Initiation in Heterogenous Explosives

Computational Simulation of Detonation Initiation in Heterogenous Explosives PDF Author: James Gambino
Publisher:
ISBN:
Category :
Languages : en
Pages : 376

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Computational Simulation of Detonation Initiation in Heterogenous Explosives

Computational Simulation of Detonation Initiation in Heterogenous Explosives PDF Author: James Gambino
Publisher:
ISBN:
Category :
Languages : en
Pages : 376

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Computer Simulation of the Shock Initiation of Detonation in Solid Explosives

Computer Simulation of the Shock Initiation of Detonation in Solid Explosives PDF Author: H. H. Schaafstal
Publisher:
ISBN:
Category :
Languages : en
Pages : 33

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Shock Initiation of Heterogeneous Explosives

Shock Initiation of Heterogeneous Explosives PDF Author: J. E. Reaugh
Publisher:
ISBN:
Category :
Languages : en
Pages : 27

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The fundamental picture that shock initiation in heterogeneous explosives is caused by the linking of hot spots formed at inhomogeneities was put forward by several researchers in the 1950's and 1960's, and more recently. Our work uses the computer hardware and software developed in the Advanced Simulation and Computing (ASC) program of the U.S. Department of Energy to explicitly include heterogeneities at the scale of the explosive grains and to calculate the consequences of realistic although approximate models of explosive behavior. Our simulations are performed with ALE-3D, a three-dimensional, elastic-plastic-hydrodynamic Arbitrary Lagrange-Euler finite-difference program, which includes chemical kinetics and heat transfer, and which is under development at this laboratory. We developed the parameter values for a reactive-flow model to describe the non-ideal detonation behavior of an HMX-based explosive from the results of grain-scale simulations. In doing so, we reduced the number of free parameters that are inferred from comparison with experiment to a single one - the characteristic defect dimension. We also performed simulations of the run to detonation in small volumes of explosive. These simulations illustrate the development of the reaction zone and the acceleration of the shock front as the flame fronts start from hot spots, grow, and interact behind the shock front. In this way, our grain-scale simulations can also connect to continuum experiments directly.

Numerical Modeling of Explosives and Propellants

Numerical Modeling of Explosives and Propellants PDF Author: Charles L. Mader
Publisher: CRC Press
ISBN: 142005239X
Category : Technology & Engineering
Languages : en
Pages : 539

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Book Description
Major advances, both in modeling methods and in the computing power required to make those methods viable, have led to major breakthroughs in our ability to model the performance and vulnerability of explosives and propellants. In addition, the development of proton radiography during the last decade has provided researchers with a major new experimental tool for studying explosive and shock wave physics. Problems that were once considered intractable – such as the generation of water cavities, jets, and stems by explosives and projectiles – have now been solved. Numerical Modeling of Explosives and Propellants, Third Edition provides a complete overview of this rapidly emerging field, covering basic reactive fluid dynamics as well as the latest and most complex methods and findings. It also describes and evaluates Russian contributions to the experimental explosive physics database, which only recently have become available. This book comes with downloadable resources that contain— · FORTRAN and executable computer codes that operate under Microsoft® Windows Vista operating system and the OS X operating system for Apple computers · Windows Vista and MAC compatible movies and PowerPoint presentations for each chapter · Explosive and shock wave databases generated at the Los Alamos National Laboratory and the Russian Federal Nuclear Centers Charles Mader’s three-pronged approach – through text, computer programs, and animations – imparts a thorough understanding of new computational methods and experimental measuring techniques, while also providing the tools to put these methods to effective use.

Initiation and Detonation of Heterogeneous High Explosives

Initiation and Detonation of Heterogeneous High Explosives PDF Author: Pier K. Tang
Publisher:
ISBN:
Category : Explosives
Languages : en
Pages : 15

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Initiation and Detonation of Heterogeneous High Explosives a Unified Model

Initiation and Detonation of Heterogeneous High Explosives a Unified Model PDF Author: P.K. Tang
Publisher:
ISBN:
Category :
Languages : en
Pages : 17

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Three Dimensional Modeling of Shock Initiation of Heterogeneous Explosives

Three Dimensional Modeling of Shock Initiation of Heterogeneous Explosives PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The basic processes in the shock initiation of heterogeneous explosives have been investigated theoretically using a model of a cube of nitromethane containing 91 cubic air holes. The interaction of a shock wave with the density discontinuities, the resulting hot spot formation and interaction, and the buildup to propagating detonation were computed using three-dimensional numerical Eulerian hydrodynamics with Arrhenius chemical reaction and accurate equations of state. The basic process in the desensitization of a heterogeneous explosive by preshocking with a shock pressure too low to cause propagating detonation was numerically modeled.

Shock Wave Science and Technology Reference Library, Vol. 5

Shock Wave Science and Technology Reference Library, Vol. 5 PDF Author: Blaine Asay
Publisher: Springer Science & Business Media
ISBN: 3540879536
Category : Technology & Engineering
Languages : en
Pages : 630

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Book Description
Los Alamos National Laboratory is an incredible place. It was conceived and born amidst the most desperate of circumstances. It attracted some of the most brilliant minds, the most innovative entrepreneurs, and the most c- ative tinkerers of that generation. Out of that milieu emerged physics and engineering that beforehand was either unimagined, or thought to be f- tasy. One of the ?elds essentially invented during those years was the science of precision high explosives. Before 1942, explosives were used in munitions and commercial pursuits that demanded proper chemistry and con?nement for the necessary e?ect, but little else. The needs and requirements of the Manhattan project were of a much more precise and speci?c nature. Spatial and temporal speci?cations were reduced from centimeters and milliseconds to micrometers and nanoseconds. New theory and computational tools were required along with a raft of new experimental techniques and novel ways of interpreting the results. Over the next 40 years, the emphasis was on higher energy in smaller packages, more precise initiation schemes, better and safer formulations, and greater accuracy in forecasting performance. Researchers from many institutions began working in the emerging and expanding ?eld. In the midst of all of the work and progress in precision initiation and scienti?c study, in the early 1960s, papers began to appear detailing the ?rst quantitative studies of the transition from de?agration to detonation (DDT), ?rst in cast, then in pressed explosives, and ?nally in propellants.

A Simplistic Approach to the Shock Initiation of Detonation in Heterogeneous Explosives

A Simplistic Approach to the Shock Initiation of Detonation in Heterogeneous Explosives PDF Author: Philip M. Howe
Publisher:
ISBN:
Category :
Languages : en
Pages : 25

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Book Description
A model of the shock initiation of heterogeneous explosives is presented. The model is based upon a 'hotspot' ignition mechanism. Choice of the energy density as the independent variable in the problem permits separation of Hugoniot effects from the buildup process, and leads to a critical condition for initiation which is independent of the loading density. The model is found to be consistent with data from the literature on porous tetryl. (Author).

Gaseous and Heterogeneous Detonations: Science to Applications

Gaseous and Heterogeneous Detonations: Science to Applications PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 380

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Book Description
This document contains twenty-four selected papers presented at the International Colloquium on Advanced Experimentation & Computation of Detonations, September 14-17 1998, St. Petersburg, Russia. The papers discuss recent advances made in understanding detonation wave initiation, propagation, mitigation and control through experimental and computational studies. The book contains five Parts: Detonation Initiation, Detonation Wave Structure and Propagation, Detonation Mitigation and Control, Applications of Detonation Phenomena, and Detonability of Advanced Fuels. The volume is intended to be a tool to explore the international state of the art and an avenue for further follow-up for the researchers and practicing engineers.