Helicopter Lifting Surface Theory with Force Free Wakes. Part II.

Abstract

Steady potential flow nonlinear lifting surface theory is applied to an arbitrary helicopter rotor system in constant rotational and constant axial translational motion including hover. An unknown velocity doublet distribtuion is imposed on both the blade and wake surfaces, satisfying the normal boundary conditions on the true wetted surface and the Kutta condition at the trailing edge. The governing equation, then, becomes a Fredholm integral equation of the first kind. A numerical scheme is developed to solve the doublet strength distribution by approximating the surface with a finite number of uniformly loaded elements and satisfying the boundary conditions at their centroids. The integral equation is thereby transformed into a system of linear algebraic equations. The solution provides the velocity magnitude and direction, and the pressures on the blade surface.

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1975
Accession Number
ADA015192

Entities

People

  • Hsi F. Chou
  • Jerome B. Fanucci

Organizations

  • West Virginia University

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Equations
  • Helicopter Rotors
  • Helicopters
  • Integral Equations
  • Integrals
  • Lifting Surfaces
  • Linear Algebraic Equations
  • Potential Flow
  • Surfaces
  • Trailing Edges

Fields of Study

  • Physics

Readers

  • Aerospace Engineering
  • Fluid Dynamics.