The Structure of an Infinitely Strong Shock Wave for Hard Sphere Molecules

Abstract

The structure of an infinitely strong shock wave (i.e., a shock wave with infinitely large upstream Mach number) is investigated on the basis of the Boltzmann equation. The velocity distribution function is expressed as a sum of a multiple of the Dirac delta function, centered at the upstream bulk velocity, and a remainder. Strong evidence that the remainder has a singularity in the molecular velocity space was provided by a previous Monte Carlo simulation for a hard-sphere gas Cercignani et a/., Phys. Fluids 11, 2757 (1999). Then, the singularity was confirmed and clarified with sufficient accuracy by a precise numerical analysis by means of a finite-difference method. More specifically, the equation for the remainder, which contains the linear collision term linearized around the delta function and the nonlinear collision term, is solved numerically for a hard-sphere gas after the nonlinear collision term is replaced by the BGK collision model. The present paper reports on the main result of this analysis.

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Document Details

Document Type
Technical Report
Publication Date
Jul 09, 2000
Accession Number
ADA400976

Entities

People

  • Carlo Cercignani
  • Kazuo Aoki
  • Shigeru Takata

Organizations

  • Kyoto University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Accuracy
  • Boltzmann Equation
  • Collisions
  • Delta Functions
  • Distribution Functions
  • Equations
  • Flow
  • Gas Dynamics
  • Mach Number
  • Molecules
  • Monte Carlo Method
  • Numerical Analysis
  • Shock
  • Shock Waves
  • Simulations
  • Waves

Fields of Study

  • Mathematics

Readers

  • Calculus or Mathematical Analysis
  • Fluid Dynamics.

Technology Areas

  • Space