冰脊间遮掩作用对冰-水拖曳力影响的实验研究  

Experimental study on the sheltering effect between ice ridges on ice-water drag force

作　　者：王爽 卢鹏[1] 祖永恒 张丽敏[1] 王庆凯[1] 李志军[1] Wang Shuang;Lu Peng;Zu Yongheng;Zhang Limin;Wang Qingkai;Li Zhijun(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《海洋学报》2022年第7期170-176,共7页

基　　金：国家自然科学基金(41922045,41876213);国家重点研发计划(2018YFA0605901);中央高校基本科研业务(DUT20GJ206)。

摘　　要：为定量研究多冰脊之间的尾流遮掩作用对海冰漂移运动的影响,物理模型试验(试验有限水深为0.45 m)测量了多冰脊拖曳力的衰减变化。冰脊模型选用底角为45°的等腰直角三角形,选取了4种入水深度、9种冰脊间距进行测量。试验得到了前后冰脊拖曳力及其比值在尾流遮掩情况下的变化规律。前冰脊拖曳力与单冰脊情况一致,与冰脊速度的平方保持线性关系;而后冰脊在间距较小时出现了反向拖曳力,随冰脊间距的增大,后冰脊拖曳系数先减小再增大至不变。前后冰脊拖曳力比值的变化规律可以用指数遮掩函数来描述,该遮掩函数与冰脊间距和入水深度有关而与流速无关。通过与现有海冰模式中的遮掩函数对比,研究结论增强了该指数公式的适用性,加强了对海冰动力学模式中遮掩函数的理解。In order to quantitatively study the sheltering effect between multiple ridges keel on sea ice drift, the laboratory experiment is carried out in a tank, which is 0.45 m deep. The shape of keel models is a triangle with 45°slope angle, 4 keel depths and 9 keel spacings are selected in the experiments. The variations of the front and back keel drag force and its ratio under wake effect is investigated. The drag force on the front keel is not affected by the back keel and keeps a linear relationship with the square of keel velocity;however, the drag force of back keel appears negative value(opposite direction) when the keel spacing is small. With the increase of the spacing the drag coefficient of the back keel first decreases and then increases to a constant. The variation of the ratio of drag forces between the front and back can be described by an exponential sheltering function, which is related to keel spacings and keel depths, and independent of keel velocity. Compared with the sheltering functions which are used in present sea ice models, the exponential formula is given and improves our understanding about sheltering function in sea ice dynamic model.

关 键 词：多冰脊 拖曳力 遮掩效应 参数化 

分 类 号：P731.15[天文地球—海洋科学] P941.62