Unsteady Aerodynamics: Application to Helicopter Noise and Vibration Sources,

Abstract

A study was conducted into the feasibility of producing aerodynamic loads of sufficient fidelity to enable a realistic acoustic signal to be derived. The need arises from the excessive blade/slap noise which results from blade/vortex interaction. A tool is required to investigate the influence of design and operational parameters as a routine procedure. For this purpose a simplified two dimensional model is developed and validated against a more sophisticated analysis. The model is extended to the rotor application where the complex wake geometry is the determining factor in the character of the loading. From the distributed transient loading an acoustic signal has been derived which has been compared with experimental data. A comprehensive correlation has not yet been performed but the preliminary results are encouraging.

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1985
Accession Number
ADP005021

Entities

People

  • T. S. Beddoes

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Acoustic Signals
  • Aerodynamics
  • Aircrafts
  • Dynamics
  • Experimental Data
  • Fluid Dynamics
  • Fluid Mechanics
  • Geometry
  • Helicopters
  • Mechanics
  • Two Dimensional
  • Unsteady Aerodynamics

Fields of Study

  • Physics

Readers

  • Acoustics.
  • Aerodynamics.
  • Computational Modeling and Simulation