【作者】 姚建喜； 邹早建； 王化明；

【Author】 YAO Jian-xi~1,ZOU Zao-jian~(1,2),WANG Hua-ming~1 (1.School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai,200240, 2.State Key Laboratory of Ocean Engineering,Shanghai Jiao Tong University,Shanghai,200030)

【机构】 上海交通大学大学船舶海洋与建筑工程学院； 上海交通大学海洋工程国家重点实验室；

【摘要】 船舶近岸壁沿岸航行时,由于船体左右两侧流场不对称,使船体受到指向岸壁的横向力和使船首偏离岸壁的转首力矩,称为岸壁效应。岸壁效应对船舶近岸航行安全性具有重要影响,是船舶操纵性研究的热点课题之一。本研究基于势流理论,采用一阶Rankine源面元法计算船舶在浅水中近岸航行时受到的横向力和转首力矩。在船体表面、自由面及岸壁表面上分布源汇来表达流体扰动速度势,通过满足这些边界面上的边界条件确定未知源强;采用Newton迭代法满足非线性自由面边界条件,而辐射条件采用自由面奇点抬高与错位技术来满足;同时,采用镜像法满足水底边界条件。在求得源强和扰动速度势后,由伯努利方程得到流场中的水动压力,进而通过船体湿表面的压力积分求得船体水动力和力矩。以沿垂直岸壁作匀速直航运动的系列60船型为例,计算了在不同水深和不同船到岸壁距离时船体所受到的横向力和转首力矩,其结果与Fluent软件计算结果进行了比较。更多还原

【Abstract】 The asymmetric flow around a ship sailing along a bank causes pressure differences between the port and starboard sides of the hull.As a result,a lateral force,mostly directed towards the bank,as well as a yaw moment pushing away the bow,will act on the ship,which are the so-called bank effects.These effects have a significant impact on navigation safety for a ship traveling along a bank;research on them is one of the hot topics of ship manoeuvrability.In this paper,a first-order Rankine source panel method based on potential theory is adopted to c alculate the lateral force and yaw moment acting on a ship sailing along a vertical bank in shallow water.The velocity potential is represented by a Rankine source distribution on the hull,free surface and bank surface.The source strengths are determined by satisfying the boundary conditions on these surfaces. The non-linear free surface conditions are satisfied by a scheme based on Newton iterative method, whereas the radiation condition is satisfied by raised panels with stagger grid above the free surface. Meanwhile,the boundary condition on bottom is satisfied by the method of images.After the source strengths and the velocity potential are determined,the hydrodynamic pressure is obtained by Bernoulli equation and the hydrodynamic force and moment acting on the hull are calculated by pressure integral over the wetted hull surface.Numerical calculations are performed for a Series 60 ship.The lateral force and the yaw moment at different water depth and distance between the ship and the bank are obtained and compared with the numerical results obtained by CFD code Fluent.更多还原