Session: 08-01-01 Risers, Pipelines & VIV

Paper Number: 104396

104396 - Investigation on Optimization of Helical Strakes Layout of Marine Riser Vortex-Induced Vibration Suppression Device 

Abstract: Helical strakes have been widely used in ocean engineering to suppress vortex-induced vibration (VIV) of risers. The safety and economy of marine risers can be effectively ensured by rationally arranging the position and coverage ratio of helical strakes. However, there is few studies on the layout of helical strakes, most of the cases adopted the scheme of covering strakes as much as possible. Such scheme will increase the cost of production and operation reducing the engineering benefits. To reveal the optimal layout scheme of helical strakes in engineering,a prediction method base on the non-iterative frequency domain is applied to investigate the VIV responses of riser under different helical strakes layout schemes in this paper. The deep neural network algorithm is further used to obtain the optimal layout scheme of helical strakes in engineering.Comparison between the prediction results and the experimental results under uniform flows and shear flows are conducted to verify the feasibility and reliability of the prediction method. Results show that the layout of helical strakes has great influence on the suppression effect of VIV. The improper arrangement of helical strakes under the specific flow will significantly amplify the VIV response. When the coverage of helical strakes reaches a certain value, the suppression efficiency will no longer increase significantly, and the drag of riser in IL direction will be significantly amplified, which may cause pipelines collision.

Keywords: Helical strakes, Vortex-induced vibration, Engineering application, Layout optimization, Marine riser

Presenting Author: Pengqian Deng Shanghai Jiao Tong University

Presenting Author Biography: The author is a phD candidate in Shanghai Jiao Tong University, majoring in experimental and numerical study of VIV.

Authors:

Pengqian Deng Shanghai Jiao Tong University
Shixiao Fu Shanghai Jiao Tong University
Mengmeng Zhang Shanghai Jiao Tong University
Haojie Ren Shanghai Jiao Tong University
Yuwang Xu Shanghai Jiao Tong University
Tongxiao Sun Shanghai Jiao Tong University