An Investigation of Shock Wave Physics via Hybrid CFD-BGK Solution Methods for Nonequilibrium Flows

Abstract

The Unified Flow Solver, a hybrid continuum-rarefied code, is used to investigate the internal structure of a normal shock wave for a Mach range of 1.55 to 9.0 for Argon, and 1.53 to 3.8 for diatomic Nitrogen. Reciprocal shock thickness, density, temperature, heat flux, and the velocity distribution function are calculated for a one-dimensional shock wave and compared with experimental data from Alsmeyer and DSMC results from Bird. Using the Euler, Navier-Stokes, BGK model, and Three-Temperature BGK model schemes, results from UFS compare well with experiment and DSMC. The Euler scheme shows atypical results, possibly resulting from modifications made to include internal energies. An entropy spot is introduced into a two-dimensional domain to investigate entropy-shock interactions over a range of Knudsen numbers (Kn=0.01, 0.1, and 1.0) for Mach 2.0 in Argon. Previous work on entropy-shock interactions has only been performed using an Euler scheme. Here, results are presented in Argon using coupled BGK and Navier-Stokes solvers. Density, pressure, and temperature profiles, as well as the profiles of their gradients, are reported at certain times after the entropy spot convects through the shock.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2009
Accession Number
ADA496219

Entities

People

  • Brook I. Bentley

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Aircrafts
  • Boltzmann Equation
  • Boundary Layer
  • Computational Fluid Dynamics
  • Computational Science
  • Distribution Functions
  • Experimental Data
  • Fluid Dynamics
  • Fluid Flow
  • Heat Flux
  • Heat Transfer
  • Knudsen Number
  • Mechanics
  • Nonequilibrium Flow
  • Physics Laboratories
  • Temperature Gradients

Fields of Study

  • Physics

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Fluid Dynamics.