Spacing effects on hydrodynamics of heave plates on offshore structures

L. Tao, B. Molin, Y. M. Scolan, K. Thiagarajan

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

The nonlinear viscous flow problem associated with a heaving vertical cylinder with two heave plates in the form of two circular disks attached is solved using a finite difference method. Numerical experiments are carried out to investigate the spanwise length effects on the hydrodynamic properties, such as added mass and damping coefficients. Over a Keulegan-Carpenter (KC) number range from 0.1 to 0.6 at frequency parameter (β = 7.869 × 107), calculations indicate that a KC-dependent critical value of spanwise length L / Dd (L-the distance between the disks, and Dd-the diameter of the disks) exists. A significant influence of L / Dd on the vortex shedding patterns around the disks and the hydrodynamic coefficients is revealed when L / Dd is smaller than the critical value due to strong interaction between vortices of different disks. Beyond that limit, however, both added mass and damping coefficients are shown to be rather stable, indicating the independence of the vortex shedding processes of different disks.

LanguageEnglish
Pages1119-1136
Number of pages18
JournalJournal of Fluids and Structures
Volume23
Issue number8
DOIs
Publication statusPublished - Nov 2007

Fingerprint

Offshore structures
Vortex shedding
Hydrodynamics
Damping
Viscous flow
Finite difference method
Vortex flow
Experiments

Keywords

  • added mass
  • heave plate
  • spar
  • viscous damping
  • vortex shedding
  • nonlinear viscous flow
  • finite difference method
  • hydrodynamic properties
  • hydrodynamic coefficients

Cite this

Tao, L. ; Molin, B. ; Scolan, Y. M. ; Thiagarajan, K. / Spacing effects on hydrodynamics of heave plates on offshore structures. In: Journal of Fluids and Structures. 2007 ; Vol. 23, No. 8. pp. 1119-1136.
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Spacing effects on hydrodynamics of heave plates on offshore structures. / Tao, L.; Molin, B.; Scolan, Y. M.; Thiagarajan, K.

In: Journal of Fluids and Structures, Vol. 23, No. 8, 11.2007, p. 1119-1136.

Research output: Contribution to journalArticle

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