剖面风速下雨场分布特性及海洋平台雨载荷计算研究

Distribution characteristics of rain field in profile wind speed and calculation of rain load on offshore platforms

海上浮式结构物不断向大型化发展,极端环境中大型海上浮式结构物的雨载荷已成为设计人员关注的焦点问题之一。本文基于离散粒子模型,开展风驱雨场运动预报,量化雨场空间特征参数分布规律;推导结构雨载荷的计算公式,完成海洋平台不同风速和降雨强度组合工况下雨载荷的预报。研究表明:采用DNV风剖面和Davenport风谱作用下的海洋平台雨载荷服从Gamma分布;相较于平均风载荷,当降雨强度R=800 mm/h时,雨载荷三一值占比为5.07%,最大值占比为8.87%;当降雨强度R=20 mm/h,雨载荷三一值占比为0.36%,最大值占比为0.6%。本文研究成果可为海上结构物及其系泊系统设计提供指导。

With the continuous development of large-scale offshore floating structures,the rain load of large scale offshore floating structures in extreme environment has become one of the focus issues of designers.Based on the discrete particle model,the motion prediction of wind driven rain field was made and the distri-bution law of spatial characteristic parameters of rain field was quantified.The calculation formula of structur-al rain load was deduced,and the rain load prediction of offshore platform under different wind speed and rainfall intensity combination conditions was completed.The research results show that the rain load of off-shore platforms under the action of DNV wind profile and Davenport wind spectrum follows Gamma distribu-tion.Compared to the average wind load,when the rainfall intensity R is 800 mm/h,the significant value of rain load accounts for 5.07%,and the maximum value accounts for 8.87%;when the rainfall intensity R is 20 mm/h,the significant value of rain load accounts for 0.36%,and the maximum value accounts for 0.6%.The research results of this paper can provide guidance for the design of offshore structures and their mooring sys-tems.