Hydrodynamics of an oscillating articulated eel-like structure

Claus Christian Apneseth, Alexander Day, David Clelland

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

This study examines the hydrodynamic performance of a highly simplified eel-like structure consisting of three articulated segments with the two aft segments oscillating. A physical model was built and tested to determine the forces developed with the model stationary, to find the self-propulsion speed, and to explore the effect on hydrodynamic performance of different swimming patterns. It was found that hydrodynamic performance increases with increasing oscillation frequency; the highest forces when stationary, and the highest self-propulsion speeds were produced by swimming patterns in which the amplitude in the aft segment is larger than that in the forward segment, and in which the motion of the aft segment lags the forward segment. A simple semi-empirical model based on Morison’s equation was implemented to predict the hydrodynamic forces. This was shown to predict mean thrust well in cases in which the aft segment oscillates in phase with the forward segment, but less reliably when the phase difference between the segments increases. Force time histories are generally not well-predicted using this approach. Nonetheless, self-propulsion speeds are predicted within 30% in all cases examined.

LanguageEnglish
Pages1221-1232
Number of pages12
JournalOcean Engineering
Volume37
Issue number13
DOIs
Publication statusPublished - Sep 2010

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Hydrodynamics
Propulsion
Swimming

Keywords

  • hydrodynamics
  • fish locomotion
  • swimming
  • model testing

Cite this

Apneseth, Claus Christian ; Day, Alexander ; Clelland, David. / Hydrodynamics of an oscillating articulated eel-like structure. In: Ocean Engineering. 2010 ; Vol. 37, No. 13. pp. 1221-1232 .
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Hydrodynamics of an oscillating articulated eel-like structure. / Apneseth, Claus Christian; Day, Alexander; Clelland, David.

In: Ocean Engineering, Vol. 37, No. 13, 09.2010, p. 1221-1232 .

Research output: Contribution to journalArticle

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