A THEORY FOR VTOL PROPELLER OPERATION IN A STATIC CONDITION

Abstract

A general theory for performance calculations was formulated based on a continuous vortex representation along the lines of the classical lifting-line model. As opposed to forward flight, the deformation of the wake is appreciable just behind the propeller, and its determination constitutes the heart of the static problem. A computer program has been developed to calculate both the inflow at the propeller and the induced velocity at any field point for an arbitrary description of the trailing vortex sheets. To approximate the force- free condition imposed on the wake, an initial wake hypothesis derived from the theory of the Generalized Actuator Disk was first used. The resulting comparisons with both detailed and gross measurements were unsatisfactory and a refined hypothesis was derived. The refined wake hypothesis provides a more reasonable representation of the 'pitch' of the elements of the deformed trailing vortex sheets as well as the envelope of their trajectories.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1965
Accession Number
AD0623527

Entities

People

  • Donald E. Ordway
  • Henry V. Borst
  • John C. Erickson Jr.
  • Richard M. Ladden

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Aircrafts
  • Classification
  • Computer Programs
  • Computers
  • Contracts
  • Figure Of Merit
  • Flow
  • Geometry
  • Governments
  • Measurement
  • Propeller Blades
  • Propeller Hubs
  • Propellers
  • Radial Velocity
  • Short Takeoff Aircraft
  • Trailing Vortices

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Fluid Dynamics.
  • Theoretical Analysis.