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Laser anemometer measurements of trailing vortices in water

Published online by Cambridge University Press:  29 March 2006

G. R. Baker
Affiliation:
Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena
S. J. Barker
Affiliation:
Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena
K. K. Bofah
Affiliation:
Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena
P. G. Saffman
Affiliation:
Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena

Abstract

A series of measurements of trailing vortices behind lifting hydrofoils is described. These measurements were made in the Caltech Free-Surface Water Tunnel, using a laser-Doppler velocimeter to measure two components of velocity in the vortex wake. Two different model planforms were tested, and measurements were made at several free-stream velocities and angles of attack for each. Velocity profiles were measured at distances downstream of the model of from five to sixty chord lengths. These measurements are the first results of a continuing experimental programme.

In § 3 of this paper, the theory of trailing vortices is discussed. The effects of ‘vortex wandering’ upon the measurements are computed, and the corrected results are seen to be in reasonable agreement with the theory.

Type
Research Article
Copyright
© 1974 Cambridge University Press

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