Talk Abstract:
Level Set Methods for Tracking Shocks in Detonation Flows
Tariq
D. Aslam
Los Alamos National Laboratory
Group DX-1, Detonation Science and Technology
aslam@lanl.gov
http://www.lanl.gov/home/aslam
A level set algorithm for tracking discontinuities in hyperbolic
conservation laws is presented. The algorithm uses a simple
finite difference approach, analogous to the method of lines
scheme presented in [1]. The zero of a level set function is
used to specify the location of the discontinuity. Since a level
set function is used to describe the front location, no extra
data structures are needed to keep track of the location of
the discontinuity. Also, two solution states are used at all
computational nodes, one corresponding to the "real"
state, and one corresponding to a "ghost node" state,
analogous to the "Ghost Fluid Method" of [2]. High-order,
point-wise convergence is demonstrated for linear and nonlinear
scalar conservation laws, even at discontinuities and in multiple
dimensions. The solutions are compared to standard high order
shock capturing schemes.
This presentation will focus on systems of conservation laws.
In particular, results of fully resolved detonation flows in
the Euler equations will be presented. It will be demonstrated
that the method can be used effectively when very accurate results
are required for problems involving shock waves.
[1] C.-W. Shu and S. Osher, "Efficient Implementation of
Essentially Non-oscillatory Shock-Capturing Schemes" Journal
of Computational Physics, 77, 439-471, 1988.
[2] R. P. Fedkiw, T. Aslam, B. Merriman and S. Osher, "A
Non-Oscillatory Eulerian Approach to Interfaces in Multimaterial
Flows (The Ghost Fluid Method)," Journal of Computational
Physics, to appear, 152, 457-492, 1999.
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1999-2000
Reactive Flow and Transport Phenomena
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