Model Studies of Helicopter Tail Rotor Flow Patterns In and Out of Ground Effect

Abstract

Water tunnel studies of a model helicopter which entailed a visualization of the main and tail rotor wakes, the inflow patterns, and their subsequent interactions as the wind velocity and wind heading were changed resulted in a significant gain in knowledge ultimately applicable to direction control of helicopters. Of significant interest was the impingement of the main rotor wake with a ground plane, its subsequent spreading outward in a radial manner and the roll-up of the wake into a standing vortex at the outer edge of this radial expansion of the wake.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1971
Accession Number
AD0725591

Entities

People

  • August F. Lehman

Tags

DTIC Thesaurus Topics

  • Aircrafts
  • Airfoils
  • Boundaries
  • Contracts
  • Directional
  • Flow Fields
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Flow
  • Helicopter Rotors
  • Model Tests
  • Photographs
  • Photography
  • Test And Evaluation
  • Test Facilities
  • Wind Tunnel Tests
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerospace Engineering
  • Fluid Mechanics and Fluid Dynamics.