Generating controllable velocity fluctuations using twin oscillating hydrofoils: experimental validation

S. F. Harding, G. S. Payne, I. G. Bryden

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

A method for generating controllable two-dimensional velocity fluctuations using two pitching foils was derived theoretically in a previous companion paper. The present work describes the experimental implementation of the method. The experiments are carried out in a re-circulating water channel optimised to provide low turbulence intensity in the incoming flow. Velocities are measured using an acoustic Doppler velocimeter (ADV). The pitching motions of the foils are position-controlled using a closed-loop control system. Two velocity fluctuation patterns are investigated. They consist of a combination of sinusoidal components. Theoretical predictions and experimental measurements are compared in the time and frequency domain. Although some discrepancies are observed, the agreement is generally good and therefore validates the theoretical method for the conditions investigated. 

LanguageEnglish
Pages113-123
Number of pages11
JournalJournal of Fluid Mechanics
Volume750
Early online date30 May 2014
DOIs
Publication statusPublished - 31 Jul 2014

Fingerprint

hydrofoils
Hydrofoils
Metal foil
foils
low turbulence
Velocimeters
Closed loop control systems
Turbulence
Acoustics
acoustics
predictions
water
Water
Experiments

Keywords

  • vortex flows
  • vortex streets
  • wakes/jets

Cite this

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Generating controllable velocity fluctuations using twin oscillating hydrofoils : experimental validation. / Harding, S. F.; Payne, G. S.; Bryden, I. G.

In: Journal of Fluid Mechanics, Vol. 750, 31.07.2014, p. 113-123.

Research output: Contribution to journalArticle

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