Some Dynamic Properties of a Rigid Two-Bladed Fully Gimballed Tip-Jet Helicopter Rotor with Circulation Control,

Abstract

Simplified analyses are carried out for the motions of a simple rigid two-bladed fully gimballed rectangular rotor rotating at constant speed about a stationary center point and about a center point translating at a low constant advance ratio. (The term 'fully gimballed' means that hub moments about all axes are zero.) It is concluded that: The rotor can be rendered dynamically stable by appropriate mass balancing. In a particular example considered, the mass balancing was estimated to increase the rotor weight by about 20%. The steady state motion about a translating center due to first harmonic moments induced by translation is a wobbling motion with the principal axis of rotation describing a cone about its mean position at twice to rotor rotational frequency. A circulation control system can control total rotor lift and can cause precession of the mean position of the principal rotational axis to any desired orientation. It cannot, however, influence the amplitude of the steady state wobble.

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1980
Accession Number
ADA094031

Entities

People

  • Harvey R. Chaplin

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aircrafts
  • Airframes
  • Amplitude
  • Control Systems
  • Frequency
  • Helicopter Rotors
  • Helicopters
  • Jet Helicopter Rotors
  • Orientation (Direction)
  • Position Finding
  • Precession
  • Rotary Wing Aircraft
  • Rotation
  • Stationary
  • Steady State
  • Translations

Readers

  • Aerodynamics.
  • Control Systems Engineering.