Evolution of a Localized Thermal Explosion in a Reactive Gas.

Abstract

Experimental observations of ignition in premixed gaseous reactants indicate that perfectly homogeneous initiation is practically unrealizable. Instead, combustion first sets in, as a rule, at small, discrete sites where inherent inhomogeneities cause chemical activity to proceed preferentially and lead to localized explosions. Combustion waves propagating away from these hot spots or reaction centers eventually envelope the remaining bulk. This study examines the spatial structure and temporal evolution of a hot spot for a model involving Arrhenius kinetics. The hot spot, characterized by peaks in pressure and temperature with little diminution in local density, is shown to have one of two possible self-similar structures. The analysis employs a combination of asymptotics and numerics, and terminates when pressure and temperature in the explosion have peaked.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1987
Accession Number
ADA189170

Entities

People

  • A. K. Kapila
  • D. Scott Stewart
  • T. L. Jackson

Tags

Communities of Interest

  • Air Platforms
  • C4I
  • Counter IED
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Blast Waves
  • Boundary Layer
  • Boundary Value Problems
  • Chemical Reaction Properties
  • Chemical Reactions
  • Combustion
  • Differential Equations
  • Equations
  • Exothermic Reactions
  • Explosions
  • Explosives
  • Gases
  • Hot Spots
  • Ignition
  • Layers
  • Reactive Gases
  • Temperature Gradients

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Theoretical Analysis.
  • Thermal Physics or Thermal Science.