Regularization of the Chapman-Enskog Expansion and Its Description of Shock Structure

Abstract

Abstract. In the continuum transition ow regime, we propose to truncate the Chapman-Enskog expansion of the Boltzmann equation to the Navier-Stokes order only without going to the Burnett or super Burnett orders. However, the local particle collision time has to be generalized to depend not only on the local macroscopic ow variables, but also their gradients in the rare ed gas regime. Based on the gas-kinetic BGK model, the relation between the conventional collision time and the general one is obtained. More specially, a generalized constitutive relation for stress and heat ux is proposed. This new model is applied to the study of argon gas shock structure. There is good agreement between the predicted shock structure and experimental results for a wide range of Mach numbers.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2001
Accession Number
ADA398622

Entities

People

  • Kun Xu

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Collisions
  • Distribution Functions
  • Equations
  • Experimental Data
  • Hong Kong
  • Kinetic Theory
  • Knudsen Number
  • Mach Number
  • Mean Free Path
  • Navier Stokes Equations
  • Particle Collisions
  • Particles
  • Prandtl Number
  • Shock
  • Shock Waves
  • Transitions
  • Viscosity

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Fluid Dynamics.