Wave Mechanics of Boundary Layer Turbulence and Noise,

Abstract

Recent advances in the understanding of the structure of boundary layer turbulence form the basis of a new conceptual model for the fluctuating velocity field. In this, an 'active' mode of small-scale motion is coupled to a large-scale 'passive' mode by aid of wave mechanical considerations. The small-scale motion originates during the intermittent 'bursting' in the wall layer leading to excitation of large-scale, damped, traveling shear waves. It is argued that the passive wave-like mode gives the major contribution to the pseudosound, whereas the active bursting mode serves as the predominant source for the radiative noise. It is shown that the bursting mode gives rise to compact noise sources of both dipole and quadrupole type whose strengths are related to the turbulent shear stress production.

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1974
Accession Number
ADA001932

Entities

People

  • Marten T. Landahl

Organizations

  • Massachusetts Institute of Technology

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Fluid Mechanics
  • Layers
  • Mechanical Properties
  • Mechanics
  • Secondary Waves
  • Shear Stresses
  • Stratified Fluids
  • Turbulence
  • Waves

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Plasma Physics / Magnetohydrodynamics