Download or read book Numerical Simulation of Deflagration to Detonation Transition in Hydrogen Explosion written by Ali Heidari 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 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 400 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 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 Numerical Simulation of Deflagration to detonation Transition written by Elaine S. Oran and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Major Research Topics in Combustion written by M.Y. Hussaini and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Institute for Computer Applications in Science and Engineer ing (ICASE) and NASA Langley Research Center (LaRC) brought together on October 2-4, 1989 experts in the various areas of com bustion with a view to expose them to some combustion problems of technological interest to LaRC and possibly foster interaction with the academic community in these research areas. The top ics chosen for this purpose were flame structure, flame stability, flame holding/extinction, chemical kinetics, turbulence-kinetics in teraction, transition to detonation, and reacting free shear layers. The lead paper set the stage by discussing the status and issues of supersonic combustion relevant to scramjet engine. Then the ex perts were called upon i) to review the current status of knowledge in the aforementioned ;:I. reas, ii) to focus on how this knowledge can be extended and applied to high-speed combustion, and iii) to suggest future directions of research in these areas. Each topic was then dealt with in a position paper followed by formal discussion papers and a general discussion involving the participants. The position papers discussed the state-of-the-art with an emphasis on key issues that needed to be resolved in the near future. The discussion papers crit ically examined these issues and filled in any lacunae therein. The edited versions of the general discussions in the form of questions from the audience and answers from the speakers are included wher ever possible to give the reader the flavor of the lively interactions that took place.
Download or read book Numerical Modeling of the Deflagration to detonation Transition written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of a confined porous bed of burning explosive in contact with a solid explosive is studied by computer simulation. The burning is modeled using a bulk burn model that is a function of the surface area and the pressure. Once pressure excursions occur from the confined burning the transition to detonation is modeled using a pressure-dependent heterogeneous explosive shock decomposition model called Forest Fire. The occurrence of detonation in the solid explosive is shown to be dependent upon the surface-to-volume ratio, the confinement of the porous bed, and the geometry of the system.
Download or read book GASFLOW MPI A Scalable Computational Fluid Dynamics Code for Gases Aerosols and Combustion Band 1 Theory and Computational Model Revision 1 0 written by Xiao, Jianjun and published by KIT Scientific Publishing. This book was released on 2016-04-06 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Karlsruhe Institute of Technology (KIT) is developing the parallel computational fluid dynamics code GASFLOW-MPI as a best-estimate tool for predicting transport, mixing, and combustion of hydrogen and other gases in nuclear reactor containments and other facility buildings. GASFLOW-MPI is a finite-volume code based on proven computational fluid dynamics methodology that solves the compressible Navier-Stokes equations for three-dimensional volumes in Cartesian or cylindrical coordinates.
Download or read book First Principles Petascale Simulations for Predicting Deflagration to Detonation Transition in Hydrogen Oxygen Mixtures written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogen has emerged as an important fuel across a range of industries as a means of achieving energy independence and to reduce emissions. DDT and the resulting detonation waves in hydrogen-oxygen can have especially catastrophic consequences in a variety of industrial and energy producing settings related to hydrogen. First-principles numerical simulations of flame acceleration and DDT are required for an in-depth understanding of the phenomena and facilitating design of safe hydrogen systems. The goals of this project were (1) to develop first-principles petascale reactive flow Navier-Stokes simulation code for predicting gaseous high-speed combustion and detonation (HSCD) phenomena and (2) demonstrate feasibility of first-principles simulations of rapid flame acceleration and deflagrationto- detonation transition (DDT) in stoichiometric hydrogen-oxygen mixture (2H2 + O2). The goals of the project have been accomplished. We have developed a novel numerical simulation code, named HSCD, for performing first-principles direct numerical simulations of high-speed hydrogen combustion. We carried out a series of validating numerical simulations of inert and reactive shock reflection experiments in shock tubes. We then performed a pilot numerical simulation of flame acceleration in a long pipe. The simulation showed the transition of the rapidly accelerating flame into a detonation. The DDT simulations were performed using BG/Q Mira at the Argonne National Laboratiory, currently the fourth fastest super-computer in the world. The HSCD is currently being actively used on BG/QMira for a systematic study of the DDT processes using computational resources provided through the 2014-2016 INCITE allocation" First-principles simulations of high-speed combustion and detonation." While the project was focused on hydrogen-oxygen and on DDT, with appropriate modifications of the input physics (reaction kinetics, transport coefficients, equation of state) the code has a much broader applicability to petascale simulations of high speed combustion and detonation phenomena in reacting gases, and to high speed viscous gaseous flows in general. Project activities included three major steps - (1) development of physical and numerical models, (2) code validation, and (3) demonstration simulation of flame acceleration and DDT in a long pipe.
Download or read book Simulations of Gas Phase Detonations written by and published by . This book was released on 1980 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detailed numerical simulations of supersonic reactive flow and gas phase detonation problems are very expensive due to their computer time and memory requirements. The bulk of this cost is in integrating the ordinary differential equations describing chemical reactions. A global induction parameter model has thus been developed which describes the chemical induction time of a mixture and allows for release of energy over a finite time period. The specific gases for which it has been calibrated are stoichiometric mixtures of hydrogen and methane in air. The relatively inexpensive induction parameter model is then used in time-dependent one- and two-dimensional simulations of supersonic reactive flows. (Author).
Download or read book OpenFOAM written by J. Miguel Nóbrega and published by Springer. This book was released on 2019-01-24 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains selected papers of the 11th OpenFOAM® Workshop that was held in Guimarães, Portugal, June 26 - 30, 2016. The 11th OpenFOAM® Workshop had more than 140 technical/scientific presentations and 30 courses, and was attended by circa 300 individuals, representing 180 institutions and 30 countries, from all continents. The OpenFOAM® Workshop provided a forum for researchers, industrial users, software developers, consultants and academics working with OpenFOAM® technology. The central part of the Workshop was the two-day conference, where presentations and posters on industrial applications and academic research were shown. OpenFOAM® (Open Source Field Operation and Manipulation) is a free, open source computational toolbox that has a larger user base across most areas of engineering and science, from both commercial and academic organizations. As a technology, OpenFOAM® provides an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to solid dynamics and electromagnetics, among several others. Additionally, the OpenFOAM technology offers complete freedom to customize and extend its functionalities.
Download or read book Numerical analysis on deflagration to detonation transition of a hydrogen oxygen mixture in a smoooth tube written by Yoshitomo Inaba and published by . This book was released on 2005 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling and Numerical Simulation of Deflagration to detonation Transition in Porous Energetic Materials written by Shaojie Xu and published by . This book was released on 1996 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: An understanding of the deflagration-to-detonation transition (DDT) in porous energetic materials is important for various engineering applications. Safety issues for damaged explosives is one example. In this work, two topics related to multi-dimensional simulation of DDT in energetic materials are presented. The objective of the first part is to develop a simple and predictive model for multidimensional simulations. Models constructed by two-phase mixture theory usually have complicated mathematical formulation, and admit complex dispersive wave structures. Three simplified single-velocity models, named BKS, SVG and GISPA, are considered in this work. The BKS model was derived--using asymptotic theory--from the two-phase theory by assuming a large interphase drag. The SVG model is newly developed, based on solid-void-gas three-phase formulation. The GISPA model is a new single-phase model which utilizes two independent rate processes for compaction and reaction. In addition to model simplification, a new reaction rate law is developed which describes the slow and the fast energy-release processes during DDT. A comparative study is carried out and the study shows that the SVG and GISPA models are able to predict all the events measured in 1-D DDT-tube experiments. The second part of the study describes the development of a high-quality numerical method for two-dimensional DDT simulations. The new fourth-order method integrates total variation diminishing and essentially non-oscillatory schemes with an extension to a general equation of state. In order to handle complex geometry, an internal boundary algorithm is developed on a structured grid, which allows a two-dimensional, non-deformable body of an arbitrary shape to be inserted in a flow field. A DDT simulation is carried out for cases of both blunt-body and sharp-body impact on porous energetic materials. The radius effect (in the case of blunt-body impact) and the angle effect (in the case of sharp-body impact) on detonation properties are studied.
Download or read book Numerical analysis on deflagration to detonation transition of a hydrogen oxygen mixture in a smooth tube written by Yoshitomo Inaba and published by . This book was released on 2005 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Combustion Flames and Explosions of Gases written by Bernard Lewis and published by Academic Press. This book was released on 2013-10-22 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion, Flames, and Explosions of Gases, Second Edition focuses on the processes, methodologies, and reactions involved in combustion phenomena. The publication first offers information on theoretical foundations, reaction between hydrogen and oxygen, and reaction between carbon monoxide and oxygen. Discussions focus on the fundamentals of reaction kinetics, elementary and complex reactions in gases, thermal reaction, and combined hydrogen-carbon monoxide-oxygen reaction. The text then elaborates on the reaction between hydrocarbons and oxygen and combustion waves in laminar flow. The manuscript tackles combustion waves in turbulent flow and air entrainment and burning of jets of fuel gases. Topics include effect of turbulence spectrum and turbulent wrinkling on combustion wave propagation; ignition of high-velocity streams by hot solid bodies; burners with primary air entrainment; and description of jet flames. The book then takes a look at detonation waves in gases; emission spectra, ionization, and electric-field effects in flames; and methods of flame photography and pressure recording. The publication is a valuable reference for readers interested in combustion phenomena.
Download or read book Numerical Simulation of Deflagration to detonation Transition on Industry Scale written by Josef Haßlberger and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Modelling of Detonation Initiation Via Shock Interaction with Multiple Flames written by Georgios Bakalis and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Detonation in gaseous mixtures is a phenomenon of great importance for explosion safety assessment in hydrogen economy and for the development of advanced detonation-based propulsion systems. In practical applications, a detonation is generally caused by a deflagration to detonation transition (DDT) since a smaller amount of energy is required compared to a direct initiation. The key issue of DDT is finding the appropriate mechanisms to rapidly generate the detonation waves with a relatively weak ignition source. The objective of this work is to study numerically the possibility of DDT resulting from shock-multiple cylindrical flames interaction. The numerical setup aims to mimic an array of laminar flames ignited at different spark times, artificially inducing chemical activity to stimulate the coupling between the gasdynamics and the chemical energy release for the transition of deflagration-to-detonation. Using numerical simulations, a number of physical parameters are varied to determine their effect on the run-up distance as well as the time until the onset of detonation occurs, and to explore any scaling relationship among different them. The two-dimensional Navier-Stokes equations with one-step Arrhenius chemistry including the effects of viscosity, thermal conduction and molecular diffusion are used for the simulations. For comparison, simulations with Euler equations are also performed. The finite-volume operator splitting scheme used is based on the 2nd order Godunov-type, Weighted Average Flux (WAF) method with an approximate HLLC Riemann Solver. An Adaptive Mesh Refinement (AMR) technique is used to increase the resolution in areas of interest. The simulation results show that the interaction of the weak shock with the first cylindrical flame demonstrates very good agreement with the results in the literature and that a single weak shock-flame interaction was not enough to cause prompt DDT. However, a high degree of Richtmyer-Meshkov instabilities induced by repeated shock-flame interactions along with shock-boundary interactions generate turbulence that accelerates the flame brush, until eventually a hot spot ignition in the unreacted material develops into a multi-headed detonation wave. The simulation results also show that DDT is sensitive to the simulation method and that certain simulation parameters significantly affect the DDT phenomenon.
Download or read book Numerical Simulations of Deflagration to Detonation Transition written by Daniele Baraldi and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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:
