Modeling and Analysis of Reactive Compaction for Granular Energetic Solids

Abstract

A technique is described for modeling mechanically induced localized heating and ignition at the grain scale (meso-scale) of granular reactive solids that maintains proper consistency with the experimentally characterized bulk (macro-scale) material behavior. The technique is illustrated for the dynamic compaction, localized heating, and ignition of granular HMX due to mild impact of a constant speed piston (^86 m/s). Guided by basic principles of contact mechanics, bulk dissipated mechanical energy is thermalized at localization sites (hot-spots) within the material meso-structure which are centered at intergranular contact points (surfaces). The evolution of bulk quantities is tracked at the macro-scale and the evolution of hot-spot temperature, mass fraction, and reaction progress are tracked at the meso-scale. Model predictions indicate that the onset of sustained combustion occurs for a piston speed that agrees well with confined Defiagration-to-Detonation Transition (DDT) experiments. This result suggests that the coupling technique may provide a rational framework for the development of improved energy localization, and ignition models for heterogeneous reactive solids. Results of a parametric sensitivity analysis show that the model is reasonably insensitive to variation in key energy localization parameters.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2001
Accession Number
ADA394713

Entities

People

  • Keith A. Gonthier

Organizations

  • Louisiana State University

Tags

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Chemical Reactions
  • Combustion
  • Conduction (Heat Transfer)
  • Energy
  • Explosions
  • Explosives
  • Heat Of Fusion
  • Hot Spots
  • Insensitive Explosives
  • Materials
  • Mechanical Energy
  • Mechanics
  • Munitions
  • Payload
  • Thermodynamics

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