Chaos and Turbulence

Abstract

The main research effort was an attempt to find low order systems possessing chaotic behavior which could successfully model turbulent flow. The reason for searching for low order systems is the strongly suggestive evidence that 'chaos' disappears in systems with a large number of degrees of freedom. Recent work on symplectic integration of Hamiltonian systems indicates that for Hamiltonian systems chaos may be no more than numerical error growing exponentially, and is absent when the numerical scheme conserves the Poincare invariants and the symplectic structure. A great deal was learned about vortical solutions of the Navier-Stokes equations and new solutions of a weakly nonlinear approximation were found, which suggest the existence of Navier-Stokes solutions which will describe a vortical description of the laminar turbulent interface. An interesting application of dynamical system theory to a problem of kinematic mixing showed that the use of these ideas could reduce the dimension of the system in order to make computations feasible, and predict the qualitative development of the distribution of mixed tracer in an unsteady flow. (edc)

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Document Details

Document Type
Technical Report
Publication Date
Aug 31, 1989
Accession Number
ADA215310

Entities

Organizations

  • California Institute of Technology

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Amplitude
  • Applied Mathematics
  • Boundary Layer
  • Channel Flow
  • Couette Flow
  • Equations
  • Flow
  • Fluid Dynamics
  • Geometry
  • Incompressible Flow
  • Mathematics
  • Pipe Flow
  • Poiseuille Flow
  • Three Dimensional
  • Turbulent Flow
  • Two Dimensional
  • Unsteady Flow

Fields of Study

  • Physics

Readers

  • Control Systems Engineering.
  • Fluid Dynamics.
  • Systems Analysis and Design