On Aeroacoustics of a Stagnation Flow Near a Rigid Wall

Abstract

We consider propagation of disturbances in a non-uniform mean flow by high order numerical simulation. Monopole and dipole acoustic, vortical and entropy pulses are embedded in an incompressible stagnation flow, which is taken as a prototype of a non-uniform low Mach number mean flow near a rigid wall at high angle of attack. Numerical results are discussed in terms of baroclinic generation of disturbance vorticity that appear to be a key process in energy transfer between a non-uniform mean flow and a propagating disturbance. These phenomena lead to amplification of sound waves originated from an acoustic pulse. Vorticity generation governs wave radiation of a near wall entropy pulse and makes the radiated waves similar to those from a vortical dipole. Interaction of initial pulse vorticity with generated vorticity leads to various radiated wave patterns discussed here.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1999
Accession Number
ADA371429

Entities

People

  • Alex Povitsky

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Propagation
  • Acoustic Waves
  • Amplitude
  • Computational Fluid Dynamics
  • Computations
  • Energy
  • Energy Transfer
  • Equations
  • Euler Equations
  • Far Field
  • Flow
  • Fluid Mechanics
  • Pressure Gradients
  • Reflection
  • Sound Waves
  • Stagnation Point
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Fluid Dynamics.