Stable Viscosities and Shock Profiles for Systems of Conservation Laws.

Abstract

Many equations of mathematical physics take the form of nonlinear hyperbolic systems of conservation laws. With small dissipative effects neglected, typically smooth solutions must develop discontinuities (shocks) in finite time. Re-incorporating dissipation helps select those discontinuities which are physically relevant. For this purpose, many different sorts of dissipation will do; in particular, the physical viscosity is typically degenerate and not convenient. In this paper the author provide an understanding of what high order viscosity terms smooth the physical discontinuities. A natural class of admissible viscosity terms is determined based on a simple linearized stability criterion. In addition, they determine a class of degenerate second order viscosity terms of physical type which are admissible. These results are applied to the equations of compressible fluid dynamics, to determine what conditions ensure the existence of the shock layer with viscosity and heat conduction. This should be of interest to others interested in general equations of state for compressible fluids, such as those investigating phase transitions.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1983
Accession Number
ADA129179

Entities

People

  • Robert L. Pego

Organizations

  • University of Wisconsin–Madison

Tags

Communities of Interest

  • Autonomy

DTIC Thesaurus Topics

  • Autonomous Systems
  • Cauchy Problem
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Discontinuities
  • Dynamics
  • Eigenvalues
  • Equations
  • Equations Of Motion
  • Equations Of State
  • Fluid Dynamics
  • Gas Dynamics
  • Mathematics
  • Navier Stokes Equations
  • Shock Waves
  • Stability Conditions

Fields of Study

  • Mathematics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Systems Analysis and Design