Nonlinear Interaction between Mean and Unsteady Flowfields near Mach 1,

Abstract

The nonlinear interaction between a steady transonic mean flow and that induced by superposed small-amplitude oscillations is studied using the method of harmonic expansions. A truncated system of spectral equations is derived which accounts for both freqeuncy and amplitude dependent changes to the mean flow, as would be induced by Reynolds stress feedback, and in particular, that owing to the primary harmonics. A three level mixed differencing scheme, comservative to leading order, is devised to solve for the nonlinearly coupled mean and unsteady disturbance flows. The harmonic method presented here is not as computationally efficient as existing ADI methods, for example, the recent scheme of Ballhaus and Goorjian, but it does yield some insight into the governing dynamical processes, and it may be useful in nonlinear flutter analyses.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1978
Accession Number
ADA060789

Entities

People

  • Wilson C. Chin

Organizations

  • Boeing Commercial Airplanes

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Amplitude
  • Boundary Layer
  • Coefficients
  • Computational Fluid Dynamics
  • Computational Science
  • Computations
  • Deflection
  • Equations
  • Feedback
  • Frequency
  • Leading Edges
  • Mach Number
  • Numerical Analysis
  • Oscillation
  • Perturbations
  • Pressure Distribution
  • Pressure Measurement

Fields of Study

  • Physics

Readers

  • Control Systems Engineering.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Fluid Mechanics and Fluid Dynamics.