An Analytical Method for Predicting Rotor Wake Geometry
Abstract:An analytical method for predicting the distorted geometry of a helicopter rotor wake is described. The development of this method is ultimately directed toward providing a more accurate aerodynamic theory for computing the instantaneous rotor flow field and associated blade airloads. It is shown that: (1) realistic self‐induced distortions of a rotor wake represented by numerous discrete vortex elements can be computed by application of the classical Biot‐Savart law and numerical integration techniques and (2) by dividing the wake into a series of near and far wake regions, the computation requirements which have previously prohibited the use of such an analysis as a cost‐effective engineering tool can be appreciably reduced. Sample comparisons of analytical and experimental wake geometries of a rotor in forward flight are presented and indicate the ability of the analysis to predict the characteristic distortion features of the wake.
Document Type: Research Article
Affiliations: Rotary Wing Technical Group, Fluid Dynamics Laboratory, United Aircraft Research Laboratories, East Hartford, Connecticut
Publication date: 1969-10-01
The Journal of the American Helicopter Society is the world's only scientific journal dedicated to vertical flight technology. It is a peer-reviewed technical journal published quarterly by AHS International and presents innovative papers covering the state-of-the-art in all disciplines of rotorcraft design, research and development. (Please note that AHS members receive significant discounts on articles and subscriptions.)
Journal subscribers who are AHS members log in here if you are not already logged in.
Authors can find submission guidelines and related information on the AHS website.