Coupled Experimental and Theoretical Investigations of Instability, Chaos and Turbulence in an Axisymmetric Jet Flow.

Abstract

The theoretical and experimental investigations on the instability, routes to chaos and transition to turbulence of an anisymmetric jet flow has been investigated. The first general task has involved the search for evidence of strange attractors in the unsteady dynamics of naturally (stochastically) and periodically excited jets. A special case of the periodically excited jets were ones having enhanced acoustic feedback. As part of this effort, substantial computer software was developed to analyse velocity time-series to determine attractor dimensions, Lyapunov exponents and topological entropy. Under conditions with strong feedback and without forcing, long highly sampled time-series were analyzed. Using independent measures of attractor dimension by a modified Grassberger-Procaccia algorithm and the singular decomposition method of Broomhead and King, the low-dimensional nature of the dynamics of the initial shear layer up to the point of pairing were confirmed. On the theoretical front, the first part of the work, now completed, dealt with the instability of thin inviscid circular shear layers.

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Document Details

Document Type
Technical Report
Publication Date
Jan 22, 1988
Accession Number
ADA192943

Entities

People

  • Hassan M. Nagib
  • Simon Rosenblat
  • Thomas C. Corke

Organizations

  • Illinois Institute of Technology

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Algorithms
  • Boundary Layer
  • Computer Programs
  • Computers
  • Differential Equations
  • Equations
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Free Stream
  • Frequency
  • Jet Flow
  • Measurement
  • Reynolds Number
  • Three Dimensional
  • Turbulent Mixing
  • Waves

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Theoretical Analysis.
  • Wave Propagation and Nonlinear Chaotic Dynamics.