Research Challenges in the Vortex-Induced Vibration Prediction of Marine Risers

Author(s):  
J. Kim Vandiver
Author(s):  
Ziqi Lu ◽  
Shixiao Fu ◽  
Mengmeng Zhang ◽  
Haojie Ren ◽  
Leijian Song

A non-iterative method in frequency domain for vortex induced vibration (VIV) predictions of marine risers is proposed in this paper. A solving model is established in modal space for predicting risers’ VIV responses, which consists of a hydrodynamic force equation and a dynamic response equation. By utilizing a non-iterative solving process in the modal space, the equations are solved without power-balance iterations. And through comparisons between this method and conventional prediction methods, the validity and applicability of this non-iterative method is verified. This method completely gets rid of the difficulty of getting convergent predictions, which is conducive to practical engineering applications and provides fresh ideas for understanding conventional empirical model methods for VIV prediction.


Author(s):  
Peter Ma ◽  
Wei Qiu ◽  
Don Spencer

Vortex-induced vibration (VIV) of marine risers poses a significant challenge as the offshore oil and gas industry moves into deep water. A time-domain analysis tool has been developed to predict the VIV of marine risers based on a forcing algorithm and by making full use of the available high Reynolds number experimental data. In the formulation, the hydrodynamic damping is not treated as a special case but simply an extension of the experimentally derived lift curves. The forcing algorithm was integrated into a mooring analysis program based on the global coordinate-based finite element method. At each time step, the added mass, lifting force, and drag force coefficients and their corresponding loads are computed for each element. Validation studies have been carried out for a full-scale rigid riser segment and a model-scale flexible riser. The numerical results were compared with experimental data and solutions by other programs.


2021 ◽  
Vol 106 (1) ◽  
pp. 147-167
Author(s):  
Dan Wang ◽  
Zhifeng Hao ◽  
Ekaterina Pavlovskaia ◽  
Marian Wiercigroch

2005 ◽  
Vol 21 (3) ◽  
pp. 335-361 ◽  
Author(s):  
A.D. Trim ◽  
H. Braaten ◽  
H. Lie ◽  
M.A. Tognarelli

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Jun Liu ◽  
Zhigang Du ◽  
Xiaoqiang Guo ◽  
Liming Dai ◽  
Liang Huang ◽  
...  

Vortex-induced vibration (VIV) is one of the most common dynamic mechanisms that cause damage to marine risers. Hamilton’s variational principle is used to establish a vortex-induced vibration (VIV) model of a flexible riser in which the wake oscillator model is used to simulate cross-flow (CF) and inline flow (IL) vortex-induced forces and their coupling, taking into account the effect of the top tension and internal flow in the riser. The VIV model is solved by combining the Newmark-β and Runge–Kutta methods and verified with experimental data from the literature. Combining Option 1 and Option 2 failure assessment diagrams (FADs) in the BS7910 standard, a fracture failure assessment model for a marine riser with circumferential semielliptical outside surface cracks is established. Using the VIV model and FAD failure assessment chart, the effects of riser length, inside/outside flows, and top tension on the VIV response and safety assessment of marine risers with outside surface cracks are investigated. It is shown that increasing the top tension can inhibit the lateral displacement amplitude and bending stress in a riser, but excessive top tension can increase the axial stress in the riser, which counteracts the decrease in the bending stress, so that the effect of top tension on crack safety is not significant. The increasing outside flow velocity significantly increases the lateral vibration amplitude and bending stress in the riser and reduces the crack safety. When other parameters remain unchanged, increasing riser length has no significant effect on the vibration amplitude of the lower part of the riser.


Author(s):  
hamed ashuri ◽  
keyvan sadeghi ◽  
saeid niazi ◽  
◽  
◽  
...  

Sign in / Sign up

Export Citation Format

Share Document