Diffusion effects near discontinuities in explosions

We investigate the problem of diffusion effects near discontinuities in TNT explosions. The model consists of gas phase conservation laws (i.e., the compressible Navier-Stokes equations), coupled with a heterogeneous continuum model for the carbon particle phase of the detonation products. The probl...

Full description

Saved in:
Bibliographic Details
Main Authors: Kuhl, Allen L., Bell, John B., Grote, David
Format: Conference Proceeding
Language:English
Subjects:
Aerodynamics
Compressibility
Computational fluid dynamics
Conservation laws
Continuum modeling
Detonation
Diffusion effects
Discontinuity
Explosions
Finite element method
Fluid flow
Grid refinement (mathematics)
Molecular diffusion
Reynolds number
Runge-Kutta method
Self-similarity
Similarity solutions
Spherical coordinates
Thermodynamic equilibrium
Vapor phases
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We investigate the problem of diffusion effects near discontinuities in TNT explosions. The model consists of gas phase conservation laws (i.e., the compressible Navier-Stokes equations), coupled with a heterogeneous continuum model for the carbon particle phase of the detonation products. The problem is assumed to be point symmetric, so 1D spherical coordinates are used. The hyperbolic terms are integrated with a 2nd-order Godunov scheme, while the viscous terms are advanced by a 2nd-order Runge-Kutta method. Adaptive Mesh Refinement is used to resolve steep gradients in the flow. A tabular EOS, based on equilibrium thermodynamics, is used for computational efficiency. Three converged solutions were found: inviscid, viscous and two-phase. The blast wave solution was self-similar (i.e., it scales with the cube root of the charge mass), however, species concentrations near the DP-Air interface and peak temperatures were smeared by molecular diffusion effects, and the shock front was smeared due to viscous effects. Similarity solutions for the latter show that diffusion effects scale with the appropriately-defined similarity functions that are related to the Peclet and Reynolds numbers of this problem.
ISSN:0094-243X
1551-7616
DOI:10.1063/12.0001094