单块浮冰在风浪流作用下的运动响应数值模拟  

Numerical Simulation of Single Ice Floe Motion Response under Actions of Wind,Wave and Current

作　　者：王亦晗 孙林华 倪宝玉[1] Wang Yihan;Sun Linhua;Ni Baoyu(College of Shipbuilding Engineering,Harbin Engineering University,Harbin 150001,China)

机构地区：[1]哈尔滨工程大学船舶工程学院,哈尔滨150001

出　　处：《水动力学研究与进展（A辑）》2024年第3期452-462,共11页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金(52192693、52192690和U20A20327)及国家重点研发计划(2021YFC2803400)。

摘　　要：随着全球气候变暖,冰缘区的浮冰数量逐渐增加,会对极地区域运行和作业的海洋结构物形成潜在威胁。为了更好地研究和预报冰缘区中的浮冰在环境载荷作用下的响应特性,该文对风浪流环境下的单块浮冰运动响应进行了数值模拟,分别研究了风拖曳工况、流拖曳工况、风浪联合作用以及波流联合作用等不同情况下的浮冰运动响应特性。在风或流的拖曳作用下,浮冰的漂移可分为初始加速和稳定漂移两个阶段,其中初始加速阶段浮冰的迎流侧出现明显的低压区,浮冰垂荡运动与纵摇运动存在相互耦合的特性。对于风或流与波浪联合作用的情况,该文采用了一种叠加波浪引起的漂移速率与拖曳引起的漂移速率的线性方法,估算了浮冰在联合作用环境下的漂移速率,此线性估算方法在风速小于7 m/s的情况下或流速低于0.08 m/s的情况下总体吻合较好。此外,该文还分析了风、流与波浪联合作用环境下浮冰纵荡、纵摇与垂荡三自由度的运动特性,并通过浮冰的漂移速率估算了波浪与浮冰的遭遇周期,其结果在风速与流速较低的情况下与数值模拟得到的浮冰各自由度运动周期结果吻合较好。With global warming,the number of ice floes increases in the marginal ice zone(MIZ),which may create threats to the marine structures in polar regions.In order to predict the response characteristics of ice floes under environmental loads in MIZ,the motion responses of a single ice floe in wind drag condition,current drag condition,wind-wave combined condition and current-wave combined condition are simulated respectively.For the former two conditions,under the drag of wind or current alone,the drift of the ice floe presents two stages:the initial accelerating stage and the stable balanced stage.During the initial accelerating stage,there is a low-pressure zone on the upstream side of the ice floe,and coupled movement characteristics between the heave motion and pitch motion arise.For the latter two conditions,a linear method using the superposition of drift velocities caused by pure wave and by drag force is adopted to estimate the ice floe drift velocity.This linear estimation method generally conforms well to the simulation results when the wind speed is less than 7 m/s or the current speed is less than 0.08 m/s.In addition,the ice floe motion responses in three degrees of freedom(surge,pitch and heave)are analyzed,in the wind-wave and current-wave combined conditions respectively.The encounter period between wave and the ice floe is estimated based on the ice floe drift velocity,and the results are in good agreement with the motion periods in various degrees of freedom in conditions with relatively low wind or current speed obtained from the numerical simulation.

关 键 词：浮冰 风浪流 运动响应 数值模拟 

分 类 号：TU476[建筑科学—结构工程]