关于m-项及三维船舶在波浪中运动的一种数值计算方法(英文)

Evaluation of the m-terms and 3D Ship Motion in Waves

文章提出一种基于Rankine源分布的三维船舶运动数值计算方法。该方法可求解定常及非定常的船舶兴波势流场。自由表面条件利用迭模解进行线性化,而物面条件中包含了m-项。由于m-项是定常速度势的物面二阶导数,数值计算有一定困难。文中使用一种直接数值差分方法计算m-项。文中也提出一种满足远方辐射条件的数值差分方法。船舶的下沉和纵倾则通过迭代求解稳态兴波问题获得,从而确定船舶在有航速时的湿表面再进行耐波性计算。该方法的计算与现有模型试验进行了比较,结果令人满意。

A 3D numerical method for ship seakeeping prediction is presented by using a Rankine source panel method. The method solves both the steady and unsteady potential flow problems. The free surface boundary condition is linearised with the double body flow, and the so called m-terms are also included in the body boundary condition. The m-terms are calculated directly by the second derivates of the velocity potential of the steady flow. A numerical scheme is also adopted to satisfy the radiation condition. The dynamic sinkage and trim are calculated by solving the steady flow prob- lem in an iteratively manner, and are used to update the wetted hull surface. The predicted results are compared with model test measurements, a fairly good agreement was found.