On Lifting-Line Theory in Unsteady Aerodynamics.

Abstract

This paper presents a linear theory of a high-aspect-ratio planar wing with a curved center line undergoing unsteady motion in an incompressible flow with a uniform freestream. Five distinct frequency ranges are identified. Except in the low-frequency range where the wave length is comparable to the wing span, matched inner and exterior solutions are obtained. The significance of the induced upwash due to sweep, and the usefulness of the center-line curvature in mitigating this upwash effect, are explained. The theory provides a basic framework wherein the lunate-tail problem in aquatic animal propulsion can be studied.

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1976
Accession Number
ADA021449

Entities

People

  • H. K. Cheng

Organizations

  • University of Southern California

Tags

DTIC Thesaurus Topics

  • Aerodynamics
  • Aspect Ratio
  • Curvature
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Frequency
  • Geometric Forms
  • Geometry
  • Incompressible Flow
  • Lines (Geometry)
  • Mechanics
  • Unsteady Aerodynamics

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Fluid Dynamics.
  • Marine Mammal Biology