Numerical Analysis of Ship Motion in Large Amplitude Waves Using a Particle Method

大振幅波浪中船舶运动的粒子法数值分析

• 批准号: 17560703
• 负责人: KOSHIZUKA Seiichi
• 金额: $ 2.24万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17560703/
• 关键词: Ship Motion; Particle Method; Rotation Angle; Quaternion; MPS Method; Computational Fluid Dynamics; Free Surface; Wave; クオータニオン; Ship Motion; Particle Method; Rotation Angle; Quaternion; MPS Method; Computational Fluid Dynamics; Free Surface; Wave; クオータニオン

The purposes of the present study are to develop a numerical method for the analysis of ship motion in large amplitude waves and to evaluate the method in comparison with experimental data. The following results are obtained.(1)Development of a numerical method to analyze ship motion in large amplitude wavesQuaternion is employed to represent the rotation angles for large motion of a ship. Quaternion has 3 degrees of freedom with 4 variables and 1 constraint condition. It has no singularity, so that it is fitted to numerical analysis. In MPS (Moving Particle Semi-implicit) method, the fluid is represented by fluid particles and the ship is represented by rigid-body particles. Motion of the fluid particles is calculated using discretized formulation of Navier-Stokes equations. The rigid-body particles are calculated by two steps.(2)Experiment analysisExperimental data of ship motion and visualized images have been obtained in a towing tank of National Maritime Research Institute. A three-dimensional numerical analysis using the present particle method is carried out with the same condition. The calculated ship motion is smaller than that predicted by the linear theory when the ratio of the wave length to the ship length is large. This is because the shipping water weight on the deck suppresses the motion. This tendency was also observed in the experiment.In conclusion, a numerical method which ca analyze the coupling between waves and large motion of a ship, and then the calculation result is compared with experimental data. The initial plan is successfully performed. The present method can also be applied to ship handling simulator in storm, ship motion in a harbor when a tsunami wave comes, ship capsizing etc.

本研究的目的是开发一种数值方法，用于分析大幅度波的船舶运动，并与实验数据相比评估该方法。 （1）开发一种数值方法来分析以大幅度波的船舶运动来代表大型船体运动的旋转角度。四元建筑具有3个自由度，有4个变量和1个约束条件。它没有奇异性，因此将其适合数值分析。在MPS（移动粒子半平均）方法中，流体由流体颗粒表示，船由刚体颗粒表示。使用Navier-Stokes方程的离散配方计算流体颗粒的运动。 （2）在国家海上研究所的牵引罐中获得了船舶运动和可视化图像的实验分析的实验分析性数据。使用本粒子方法进行的三维数值分析以相同的条件进行。计算出的船舶运动小于线性理论所预测的，当波长与船长的比率很大时。这是因为甲板上的运输水重抑制了运动。在实验中也观察到了这种趋势。结论是一种数值方法，该方法分析了波和船舶大型运动之间的耦合，然后将计算结果与实验数据进行了比较。最初的计划已成功执行。目前的方法也可以应用于暴风雨中的船舶处理模拟器，当海啸浪潮到来时，船只在港口中的船舶运动，船舶倾斜等。