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|Title:||Modeling and numerical simulation of deflagration-to-detonation transition in porous energetic materials|
|Doctoral Committee Chair(s):||Stewart, Donald S.|
|Department / Program:||Applied Mechanics
Mechanical Science and Engineering
|Discipline:||Theoretical and Applied Mechanics|
|Degree Granting Institution:||University of Illinois at Urbana-Champaign|
|Abstract:||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.
|Rights Information:||Copyright 1996 Xu, Shaojie|
|Date Available in IDEALS:||2011-05-07|
|Identifier in Online Catalog:||AAI9702720|
This item appears in the following Collection(s)
Graduate Dissertations and Theses at Illinois
Graduate Theses and Dissertations at Illinois
Dissertations and Theses - Mechanical Science and Engineering