Study on the VIV for Multiple Riser System

2016 Fiscal Year Final Research Report

• Project/Area Number: 26289343
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Naval and maritime engineering
• Research Institution: National Institute of Maritime, Port and Aviation Technology
• Principal Investigator: FUJIWARA Tomo 国立研究開発法人海上・港湾・航空技術研究所, その他部局等, 研究員 (70511591)
• Co-Investigator(Kenkyū-buntansha): 高橋 一比古 国立研究開発法人海上・港湾・航空技術研究所, その他部局等, 研究員 (30425748) ; 尾崎 雅彦 東京大学, 新領域創成科学研究科, 教授 (30529706)
• Research Collaborator: YAMAMOTO Hiroya
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 海洋開発 / 海底鉱物資源 / ライザー / 水中線状構造物 / VIV / 水槽試験

Outline of Final Research Achievements

The riser system for using oil/gas development or offshore mining development is planning the multiple riser system for improving production efficiency and securing redundancy. We have studied practical method for analyzing vortex excitation behavior in tidal current for a system consisting of multiple pieces and close proximity arrangement where hydro-dynamically mutual interference occurs.
As a result of our research, we showed that the behavior in the current changes with the flow direction and the distance between cylinders. And the behavior can be classified into several vibration patterns. In addition, a fluid force measuring device corresponding to each vibration pattern was developed and a fluid force measurement test was conducted.
Furthermore, we developed a test apparatus that reproduces the twist of the two pipe constrained by the spacer. Experimentally showed that the vortex induced vibration behavior may increase the twisting motion of the two tied pipes.

Free Research Field

海中・海底工学