兴波阻力数值预报方法研究及其在集装箱船船型优化中的应用

A research on numerical prediction method for wave-making resistance and its application to container ship hull form optimization

集装箱船作为一种中高速船,其兴波阻力在总阻力中所占比例较高。从某种意义上讲,船型优化就是寻求最小兴波阻力的船型。本文采用基于势流理论的面元法预报集装箱船的兴波阻力,对两种计算兴波阻力的方法进行了研究比较:第一种是改进的Dawson方法,传统的Dawson方法采用静水面上的叠模流线网格,而改进的Dawson方法是采用静水面上的贴体网格来计算兴波阻力;第二种方法是单模流动法。文中利用这两种方法计算了两条集装箱船,通过和试验值比较,发现这两种方法在设计航速附近的一定范围内都能正确地识别船型变化对兴波阻力的影响,验证了这两种数值预报方法都可以用于船型优化。但是改进的Dawson方法的计算结果更接近实验值,因此改进的Dawson方法更适用于船型优化。

The container ship is a kind of ship with medium or high speed, its wave-making resistance covers a great proportion of the total resistance. Under certain circumstance, hull form optimization is to look for the ship with lowest wave-making resistance. In this paper, two methods based on potential theory are developed to calculate wave-making resistance of container ship： one is the improved Dawson metbod,traditional Dawson method uses double model streamline grids on the undisturbed water surface, while the improved Dawson method uses body fitted grids; another is single model flow method. Both methods simulate the wave-making phenomena by Rankine sources distributed on hull surface and free water surface. Furthermore, the two methods are applied to calculate wave-making resistance of two container ships. Comparison to experimental data shows that both methods can correctly distinguish the influence of hull form change on wave-making resistance within the some scope of design speed. It can be concluded that the two methods are applicable to hull form optimization. But the calculation resuits of improved Dawson method are closer to experimental data, so it is more suitable for hull form optimization.