Aeroelastic Rotor Stability Analysis

Abstract

This report describes an aeroelastic analysis that provides a complete description of the dynamics and aerodynamics of fully coupled helicopter main or tail rotor/airframe/control systems. The analysis is designed to study stability characteristics in conditions of pure axial flow or in forward flight, for which it computes the systems eigenvalues and eigenvectors. For hover studies, the aerodynamic derivatives include stall and compressibility effects, and circulatory and noncirculatory unsteady effects are accounted for through use of Theodorsen and Loewy type lift deficiency functions. The forward- flight aerodynamic derivatives are obtained from any appropriate linear or nonlinear time history analysis. The approximations made in the forward-flight analysis limit such applications to an advance ratio of about 0.5.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1976
Accession Number
ADA020871

Entities

People

  • Robert A. Johnston
  • S. J. Cassarino

Organizations

  • United Technologies Corporation

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aerodynamic Forces
  • Aircrafts
  • Airframes
  • Axial Flow
  • Birds
  • Computer Programs
  • Control Systems
  • Dynamic Response
  • Equations
  • Equations Of Motion
  • Frequency
  • Helicopters
  • Mechanics
  • Modulus Of Elasticity
  • Moment Of Inertia
  • Physical Properties
  • Unsteady Aerodynamics

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Aerospace Engineering
  • Control Systems Engineering.