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On vortex shedding and prediction of vortex-induced vibrations of circular cylinders

Abstract

In offshore installations, many crucial components can be classified as slender marine structures: risers, mooring lines, umbilicals and cables, pipelines. This thesis studies the vortex shedding phenomenon and the problem of predicting vortex-induced vibrations of such structures. As the development of hydrocarbons move to deeper waters, the importance of accurately predicting the vortex-induced response has increased and so the need for proper response prediction methods is large. This work presents an extensive review of existing research publications about vortex shedding from circular cylinders and the vortex-induced vibrations of cylinders and the different numerical approaches to modelling the fluid flow. The response predictions from different methods are found to disagree, both in response shapes and in vibration amplitudes. This work presents a prediction method that uses a fully three-dimensional structural finite element model integrated with a laminar two-dimensional Navier-Stokes solution modelling the fluid flow. This solution is used to study the flow both around a fixed cylinder and in a flexibly mounted one-degree-of-freedom system. It is found that the vortex-shedding process (in the low Reynolds number regime) is well described by the computer program, and that the vortex-induced vibration of the flexibly mounted section do reflect the typical dynamic characteristics of  More>>
Publication Date:
Dec 31, 1997
Product Type:
Thesis/Dissertation
Report Number:
NEI-NO-1049
Reference Number:
SCA: 661300; PA: NW-99:005086; EDB-99:043678; SN: 99002075272
Resource Relation:
Other Information: TH: Thesis (Dr.ing.); PBD: 1997
Subject:
66 PHYSICS; OFFSHORE OPERATIONS; OFFSHORE PLATFORMS; MECHANICAL STRUCTURES; CABLES; PIPELINES; FLUID FLOW; VORTEX FLOW; MECHANICAL VIBRATIONS; HYDRODYNAMICS; NUMERICAL SOLUTION; NAVIER-STOKES EQUATIONS; COMPUTERIZED SIMULATION
OSTI ID:
328147
Research Organizations:
Norges teknisk-naturvitenskapelige univ., Trondheim (Norway)
Country of Origin:
Norway
Language:
English
Other Identifying Numbers:
Other: ON: DE99733779; ISBN 82-471-0076-2; TRN: NO9905086
Availability:
OSTI as DE99733779
Submitting Site:
NW
Size:
270 p.
Announcement Date:

Citation Formats

Halse, Karl Henning. On vortex shedding and prediction of vortex-induced vibrations of circular cylinders. Norway: N. p., 1997. Web.
Halse, Karl Henning. On vortex shedding and prediction of vortex-induced vibrations of circular cylinders. Norway.
Halse, Karl Henning. 1997. "On vortex shedding and prediction of vortex-induced vibrations of circular cylinders." Norway.
@misc{etde_328147,
title = {On vortex shedding and prediction of vortex-induced vibrations of circular cylinders}
author = {Halse, Karl Henning}
abstractNote = {In offshore installations, many crucial components can be classified as slender marine structures: risers, mooring lines, umbilicals and cables, pipelines. This thesis studies the vortex shedding phenomenon and the problem of predicting vortex-induced vibrations of such structures. As the development of hydrocarbons move to deeper waters, the importance of accurately predicting the vortex-induced response has increased and so the need for proper response prediction methods is large. This work presents an extensive review of existing research publications about vortex shedding from circular cylinders and the vortex-induced vibrations of cylinders and the different numerical approaches to modelling the fluid flow. The response predictions from different methods are found to disagree, both in response shapes and in vibration amplitudes. This work presents a prediction method that uses a fully three-dimensional structural finite element model integrated with a laminar two-dimensional Navier-Stokes solution modelling the fluid flow. This solution is used to study the flow both around a fixed cylinder and in a flexibly mounted one-degree-of-freedom system. It is found that the vortex-shedding process (in the low Reynolds number regime) is well described by the computer program, and that the vortex-induced vibration of the flexibly mounted section do reflect the typical dynamic characteristics of lock-in oscillations. However, the exact behaviour of the experimental results found in the literature was not reproduced. The response of the three-dimensional structural model is larger than the expected difference between a mode shape and a flexibly mounted section. This is due to the use of independent hydrodynamic sections along the cylinder. The predicted response is not unrealistic, and the method is considered a powerful tool. 221 refs., 138 figs., 36 tabs.}
place = {Norway}
year = {1997}
month = {Dec}
}