Turbulent Shear Flows in Laser Nozzles and Cavities.

Abstract

An invariant second-order closure program for compressible, turbulent, reacting shear flows is being developed. The development of models for the third and higher-order correlations that appear in the transport equations has been completed. A 'typical eddy' box model has been developed for computation of higher-roder scalar correlations involving species, temperatures and reaction rate fluctuations. A single species second-order closure program for compressible shear flows has been applied to study a simulation of the mixing region in a HF chemical laser. Considerable insight into the complex processes occurring in laser cavities has been achieved. The results show that the assumptions used in the eddy viscosity and the turbulent kinetic energy closure methods are not completely valid for nonequilibrium flows such as in the chemical laser system. The results of studies of other shear flows with the same invariant second-order model are in generally good agreement with experimental measurements. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1974
Accession Number
ADA000572

Entities

People

  • Ashok K. Varma
  • E. Stokes Fishburne
  • Robert A. Beddini
  • Roger D. Sullivan

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Boltzmann Equation
  • Chemical Lasers
  • Equations
  • Flow
  • Kinetic Energy
  • Laser Resonators
  • Lasers
  • Nonequilibrium Flow
  • Shear Flow
  • Viscosity

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Linear Algebra
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy