A dynamic model of deep water riser and its global response characteristics induced by ocean internal wave and floating platform

ABSTRACT

Because the flow direction of the water above and below the interface of internal wave is opposite, internal wave has a strong shear effect on ocean structures. A dynamic model of internal wave acting on deep water steel catenary riser (DSCR) is built. The global dynamic responses of gas riser and oil riser under the same action of internal wave are both obtained through numerical calculation, and the dynamic response laws of some specified positions are also studied. Then, the maximum value of dynamic response in a certain period of time and its location on the riser is found. At last, the response characteristic of DSCR induced by internal wave is studied in detail when the heave amplitude of floating platform is constant, but the heave frequency changes continuously as well as that the heave frequency is constant, but the heave amplitude changes continuously by some dynamic model experiments.

KEYWORDS:

• Riser model
• internal wave action
• dynamic response
• platform influence
• shear failure

Acknowledgements

We deeply appreciate the reviewers’ insightful comments and suggestions, which helped a lot in improving the present paper.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work is supported by the science and technology innovation Program of Hunan Province-Natural Science Foundation of Hunan Province [No: 2019JJ50684; 2019JJ40324], Scientific Research Foundation of Hunan Provincial Education Department [No: 16B029; 18C0776; 18A372; 19A047], and National Natural Science Foundation of China [No: 51875051].