EDDY MACH WAVE NOISE FROM A SIMPLIFIED MODEL OF A SUPERSONIC MIXING LAYER.

Abstract

A simplified flow model is presented for simulating features of noise generation by supersonic jets and rockets. 'Eddy Mach waves' appear as a consequence of balancing internal and external pressures, and noise power may be estimated. Specifically, the turbulent mixing layer of a supersonic jet is modeled as a layer of two-dimensional square 'eddies'; this separates the main flow from fluid at rest and moves at an intermediate speed. (In an improved model the square eddies are replaced by a turbulent flow layer constrained by plane interfaces). The initially plane interfaces, because of unopposed internal pressures, will ripple slightly such that Mach waves arise and effect a pressure balance. The Mach wave noise pattern is readily calculated as well as the acoustic energy flux. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1969
Accession Number
AD0700775

Entities

People

  • H. S. Ribner

Organizations

  • University of Toronto

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Demographic Cohorts
  • Flow
  • Internal Pressure
  • Mixing
  • Turbulent Flow
  • Turbulent Mixing
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Acoustics.
  • Coastal Oceanography
  • Fluid Dynamics.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flow