Download or read book Modeling Two dimensional Detonations with Detonation Shock Dynamics written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In any explosive device, the chemical reaction of the explosive takes place in a thin zone just behind the shock front. The finite size of the reaction zone is responsible for: the pressure generated by the explosive being less near the boundaries, for the detonation velocity being lower near a boundary than away from it, and for the detonation velocity being lower for a divergent wave than for a plane wave. In computer models that are used for engineering design calculations, the simplest treatment of the explosive reaction zone is to ignore it completely. Most explosive modeling is still done this way. The neglected effects are small when the reaction zone is very much smaller than the explosive's physical dimensions. When the ratio of the explosive's detonation reaction-zone length to a representative system dimension is of the order of 1/100, neglecting the reaction zone is not adequate. An obvious solution is to model the reaction zone in full detail. At present, there is not sufficient computer power to do so economically. Recently we have developed an alternative to this standard approach. By transforming the governing equations to the proper intrinsic-coordinate frame, we have simplified the analysis of the two-dimensional reaction-zone problem. When the radius of curvature of the detonation shock is large compared to the reaction-zone length, the calculation of the two-dimensional reaction zone can be reduced to a sequence of one-dimensional problems. 9 refs., 5 figs.

Download or read book Modeling Explosions and Blast Waves written by K. Ramamurthi and published by Springer Nature. This book was released on 2021-06-19 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: b="" The book provides a concise description of the physical processes and mathematical models for explosions and formation of blast waves from explosions. The contents focus on quantitatively determining the energy released in the different types of explosions and the destructive blast waves that are generated. The contribution of flames, detonations and other physical processes to the explosion phenomenon is dealt with in detail. Gaseous and condensed phase explosions are discussed and the yield of explosions with their TNT equivalence is determined. Time scales involved in the explosion process and the scaling procedure are ascertained. Explosions over the ground, in water, and the interaction of explosions with objects are examined. In order to keep the text easily readable, the detailed derivation of the mathematical equations is given in the seven appendices at the end of the book. Case studies of various explosions are investigated and simple problems and their solutions are provided for the different topics to assist the reader in internalizing the explosion process. The book is a useful reference for professionals and academics in aeronautics, mechanical, civil and chemical engineering and for personnel working in explosive manufacture and high-energy materials, armaments, space, defense, and industrial and fire safety.

Download or read book Instability of Steady and Quasi steady Detonations written by Brian D. Taylor and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The stability properties and dynamic behavior of steady and quasi-steady detonation theories are investigated through linear stability analysis and numerical simulation. A general, unsteady, three-dimensional formulation of the reactive Euler equations in a shock-fitted reference frame is derived. The formulation is specialized to three configurations: planar one-dimensional detonation, radially symmetric one-dimensional detonation, and two-dimensional detonation in a rectangular channel. High-order convergent numerical simulation schemes for these configurations are derived and used to study the linear and nonlinear stability of detonations. Shock-fitted numerical simulation is used to study the two-dimensional instability of steady solutions to the Zel'dovich, von Neumann, and Doring (ZND) model of detonation. It is demonstrated through several methods of analysis that the dependence of instability growth rates and oscillation frequencies on the initial disturbance wavelength, as predicted by linear stability theory, is quantitatively reproduced by shock-fitted simulations. Agreement with the theorized temporal and spatial structure of the instability is demonstrated by a functional expansion of the solution perturbations, obtained from simulation data, in terms of the linear stability eigenfunctions. Three regimes of unstable behavior - linear, weakly non-linear, and fully non-linear - are explored and characterized in terms of the power spectrum of the normal detonation velocity. Using solutions obtained from Detonation Shock Dynamics (DSD) theory, the behavior of cylindrically and spherically expanding symmetric detonations is studied by one-dimensional shock-fitted numerical simulation. We consider idealized models of gaseous and condensed phase detonation, as well as a realistic model calibrated for the high explosive PBX-9501. We study the behavior of detonations initialized with solutions of DSD as they expand radially. The various models and calibrations exhibit regimes of hydrodynamic stability, in which the detonation evolves slowly in time and agreement with DSD theory is good, and regimes of instability, which in some cases leads to failure of the detonation wave.

Download or read book Detonation Phenomena of Condensed Explosives written by Shiro Kubota and published by Springer Nature. This book was released on 2023-01-13 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents fundamental theory of shock and detonation waves as well as selected studies in detonation research in Japan, contributed by selected experts in safety research on explosives, development of industrial explosives, and application of explosives. It also reports detonation research in Japan featuring industrial explosives that include ammonium nitrate-based explosives and liquid explosives. Intended as a monographic-style book, it consistently uses technical terms and symbols and creates organic links between various detonation phenomena in application of explosives, fundamental theory of detonation waves, measurement methods, and individual studies. Among other features, the book presents a historical perspective of shock wave and detonation research in Japan, pedagogical materials for young researchers in detonation physics, and an introduction to works in Japan, including equations of state, which are worthy of attention but about which very little is known internationally. Further, the concise pedagogical chapters also characterize this book as a primer of detonation of condensed explosives and help readers start their own research.

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 Transactions of the Army Conference on Applied Mathematics and Computing written by and published by . This book was released on 1989 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Parallel Algorithms Applied to Problems in Two Dimensional Detonation Shock Dynamics written by Alberto M. Hernandez and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This design and applications project consists in the development of a parallel extension for a two-dimensional Detonation Shock Dynamics code, and to demonstrate how it can be applied for solving engineering problems in detonation physics. Detonation Shock Dynamics (DSD) is an asymptotic theory that describes the evolution of a multidimensional curve detonation shock in terms of an intrinsic evolution equation for the shock surface. Full-LS-DSD2D is a full level set Detonation Shock Dynamics code in Fortran 77 written by Dr. John Bdzil specifically for this project. A level set function numerical algorithm which embeds the two-dimensional detonation front in a three-dimensional filed function, phi(x,y,t), is used to solve for the location of the detonation front, which is given by phi(x,y,t) = 0. The code solves a modified Level Set PDE which maintains phi(x,y,t) as a distance function and uses a fully explicit. A parallel extension of the code was designed, IPC-DSD2D (Illinois Parallel Cluster DSD2D), as a Message Passing model using an MPI interface. IPC-DSD2D was benchmarked for scalability, accuracy and overall performance. Benchmarking was performed on a vertical rate stick problem that had ideal load balancing properties. The test problem was run on three different computer architectures: the Turing Cluster at the University of Illinois Urbana-Champaign, an eight core Macintosh Mac Pro, and NCSA0́9s SGI Altix (Cobalt).The benchmarking of the code showed very good performance metrics; the speedup and efficiency where high, and behaved in a stable and predictable pattern. After the code was verified and tested for performance and efficiency, it was used in a shape optimization study. A multicomponent nonlinear optimization system was built to generate optimal, shaped charge geometries using Detonation Shock Dynamics. The idea was to use IPC-DSD2D to estimate the shock pressure along a shaped charge liner and the normal shock velocity at the apex of the liner. These flow variables were then to be used as inputs for a Lagrangian finite element code to determine the shape of the jet that is formed by the detonation shock pressure crushing the liner. Through a set of constrained objective functions, a nonlinear optimizer, a shape can be found that has optimal jet properties. By running a DSD simulation of a simplified shaped charge, it was successfully shown how DSD could be used in the design of shaped charges. This thesis only describes the optimization system, and did not simulate the design loop. This thesis is divided into ten chapters. Chapters 1 and 2 briefly describe the theory of DSD and some necessary concepts in parallel computing design. Chapters 3 through 5 talk about the mathematical and numerical model used in DSD2D, and the parallel implementation of the code. Chapter 6 shows numerical results using IPC-DSD2D and Chapter 7 shows the parallel benchmarking of the code using the three computer architectures mentioned earlier. Chapter 8 describes the optimization system using DSD to find optimal shape charge geometries. Chapter 9 shows how to extend IPC-DSD2D for a three-dimensional DSD code [5]. Chapter 10 has the conclusions and final thoughts about the parallel implementation of Full-LS-DSD2D and the optimization system for designing shape charges using DSD.

Download or read book Shock Waves Science and Technology Library Vol 6 written by F. Zhang and published by Springer Science & Business Media. This book was released on 2012-03-28 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, as a volume of the Shock Wave Science and Technology Reference Library, is primarily concerned with the fundamental theory of detonation physics in gaseous and condensed phase reactive media. The detonation process involves complex chemical reaction and fluid dynamics, accompanied by intricate effects of heat, light, electricity and magnetism - a contemporary research field that has found wide applications in propulsion and power, hazard prevention as well as military engineering. The seven extensive chapters contained in this volume are: - Chemical Equilibrium Detonation (S Bastea and LE Fried) - Steady One-Dimensional Detonations (A Higgins) - Detonation Instability (HD Ng and F Zhang) - Dynamic Parameters of Detonation (AA Vasiliev) - Multi-Scaled Cellular Detonation (D Desbordes and HN Presles) - Condensed Matter Detonation: Theory and Practice (C Tarver) - Theory of Detonation Shock Dynamics (JB Bdzil and DS Stewart) The chapters are thematically interrelated in a systematic descriptive approach, though, each chapter is self-contained and can be read independently from the others. It offers a timely reference of theoretical detonation physics for graduate students as well as professional scientists and engineers.

Download or read book Dynamics of Detonations and Explosions written by and published by AIAA. This book was released on 1991 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Detonation Phenomenon written by John H. S. Lee and published by Cambridge University Press. This book was released on 2008-06-30 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the detonation phenomenon in explosives. It is ideal for engineers and graduate students with a background in thermodynamics and fluid mechanics. The material is mostly qualitative, aiming to illustrate the physical aspects of the phenomenon. Classical idealized theories of detonation waves are presented first. These permit detonation speed, gas properties ahead of and behind the detonation wave, and the distribution of fluid properties within the detonation wave itself to be determined. Subsequent chapters describe in detail the real unstable structure of a detonation wave. One-, two-, and three-dimensional computer simulations are presented along with experimental results using various experimental techniques. The important effects of confinement and boundary conditions and their influence on the propagation of a detonation are also discussed. The final chapters cover the various ways detonation waves can be formed and provide a review of the outstanding problems and future directions in detonation research.

Download or read book Proceedings written by and published by . This book was released on 1989 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt: Papers presented in this publication cover special problems in the field of energetic materials, particularly detonation phenomena in solids and liquids. General subject areas include shock-to-detonation transition, time resolved chemistry, initiation modeling, deflagration-to-detonation transition, equation of state and equation of state and performance, composites and emulsions, and composites and emulsions/underwater explosives, reaction zone, detonation wave propagation, hot spots, detonation products, chemistry and compositions, and special initiation.

Download or read book Dynamics of Shock Waves Explosions and Detonations written by J. Raymond Bowen and published by . This book was released on 1984 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On the Quasi One dimensional Structure of Two dimensional Cellular Detonations in a Duct written by Christopher Uyeda and published by . This book was released on 2015 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adaptive mesh refinement combined with a WENO-TCD hybrid numerical method are used to simulate cellular detonations in ducts using a detailed chemical mechanism linked to the inviscid Euler equations. Using this computational setup, we were able to reproduce the detonation cells and structure that other researchers have produced in their work and then used the results to validate what is called the cross-current dynamics theory, developed by Kurosaka & Tsuboi (2014). This theory uses the conservation laws, Rankine-Hugoniot jump condition, and detonation front curvature to determine the velocity directly behind the detonation front. Comparisons of the velocity ratio calculated from the cross-current dynamics theory and the data from the simulation verify the accuracy of the theory. Next we simulate a detonation propagating from the closed end of a duct and compare the one-dimensional ZND solution, which we used to initiate the two-dimensional detonations, to the area-averaged properties and the properties of particles tracked along their pathlines from the detonation front to their sonic points. Despite the complex structures that appear within the detonation, the one-dimensional solution proves to also model the structure of the area-averaged and particle properties. Disagreements between the particle properties and the one-dimensional solution are concentrated near the detonation front where the transverse wave and Mach stem introduce larger jumps in the flow properties than in the one-dimensional case. We also show the particle pathlines are dominated by a one-dimensional motion with slight drifts in the vertical direction downstream from the detonation front. By reviewing the particles' v-velocity to u-velocity ratio in the reference frame attached to the detonation front, we observe the quick transition the particles experience from a two-dimensional to a quasi one-dimensional motion. These findings give us new found appreciation of the quasi one-dimensional nature of two-dimensional detonations.

Download or read book Skilehrerb chlein f r patentierte Skilehrer des Kantons Graub nden written by and published by . This book was released on with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Aspects of Detonations written by A. L. Kuhl and published by AIAA. This book was released on 1993 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rock Fracture and Blasting written by Zong-Xian Zhang and published by Butterworth-Heinemann. This book was released on 2016-04-26 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rock Fracture and Blasting: Theory and Applications provides the latest on stress waves, shock waves, and rock fracture, all necessary components that must be critically analyzed to maximize results in rock blasting. The positioning of charges and their capacity and sequencing are covered in this book, and must be carefully modeled to minimize impact in the surrounding environment. Through an explanation of these topics, author Professor Zhang’s experience in the field, and his theoretical knowledge, users will find a thorough guide that is not only up-to-date, but complete with a unique perspective on the field. Includes a rigorous exposition of Stress Waves and Shock Waves, as well as Rock Fracture and Fragmentation Provides both Empirical and Hybrid Stress Blasting Modeling tools and techniques for designing effective blast plans Offers advanced knowledge that enables users to choose better blast techniques Includes exercises for learning and training in each chapter