上海交通大学学报(自然版) ›› 2018, Vol. 52 ›› Issue (9): 1009-1016.doi: 10.16183/j.cnki.jsjtu.2018.09.001

• 学报(中文) •    下一篇

非线性畸形波所致的平台底部砰击载荷及结构响应数值模拟

秦浩,唐文勇,薛鸿祥   

  1. 上海交通大学 海洋工程国家重点实验室; 高新船舶与深海开发装备协同创新中心, 上海 200240
  • 出版日期:2018-09-28 发布日期:2018-09-28
  • 通讯作者: 唐文勇, 男, 教授, 博士生导师, E-mail:wytang@sjtu.edu.cn.
  • 作者简介:秦浩(1990-), 男, 山东省烟台市人, 博士生, 主要研究方向为畸形波与海洋结构物相互作用.
  • 基金资助:
    国家自然科学基金资助项目(51239007)

Numerical Simulations of Impact Loads and Structural Responses of Bottom Decks of Platforms Caused by Nonlinear Freak Waves

QIN Hao,TANG Wenyong,XUE Hongxiang   

  1. State Key Laboratory of Ocean Engineering; Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai Jiao Tong University, Shanghai 200240, China
  • Online:2018-09-28 Published:2018-09-28

摘要: 基于求解2维N-S方程和流体体积(VOF)法建立数值水槽,采用Peregrine呼吸子解模型进行非线性畸形波的造波,采用2维有限元法对平台下甲板结构离散,并以一种流固耦合算法针对非线性畸形波平台底部砰击进行数值模拟.计算了该砰击问题中非线性畸形波引起的砰击载荷,并揭示了其与相同波高、波长2阶规则波引起砰击载荷的不同.考虑平台下甲板结构为弹性体的结构响应,在平台下甲板结构存在垂向初速度的条件下得到了平台下甲板结构位移时历,并采用快速傅里叶变换(FFT)对频率响应进行了分析.

关键词: 非线性畸形波, Peregrine呼吸子解, 流固耦合, 结构响应, 平台底部砰击

Abstract: In order to study the impact on offshore platforms caused by nonlinear freak waves, a numerical wave tank is built, in which the incompressible Navier-Stokes equations are solved, with the free surfaces reconstructed using a VOF method. Nonlinear freak waves based on the Peregrine breather solution are generated. A fluid-structure interaction (FSI) algorithm is used to calculate the structural response of the bottom deck, which is discretized with the finite element method (FEM). The impact loads underneath a platform model are calculated and compared with the ones caused by the 2nd-order regular waves with the same wave lengths and heights to reveal the unique features of the impact caused by nonlinear freak waves. The structural response of the bottom deck is calculated using the FSI algorithm and processed with an FFT method to analyze the wetted vibration. Additionally, the influence of the vertical initial velocity is considered during the structural response simulations.

Key words: nonlinear freak wave, Peregrine breather, fluid-structure interaction (FSI), structural response, impact underneath the bottom deck

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