部分反射直墙前二维物体的绕射和辐射问题  

The diffraction and radiation issues of 2D objects in front of partially reflective vertical walls

作　　者：滕斌[1] 赵正阳 TENG Bin;ZHAO Zhengyang(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：《海洋工程》2024年第2期1-11,共11页The Ocean Engineering

基　　金：国家重点研发计划资助项目(2021YFB2601100)。

摘　　要：基于映像理论将部分反射直墙前物体的散射问题,等效于开敞水域中原物体的散射和关于直墙映像体散射的线性叠加进行求解。采用高阶边界元方法建立了部分反射直墙前二维任意形状物体波浪绕射和辐射问题的数值分析模型,通过与已发表的海底方箱和淹没圆柱结果的对比验证了数值模型的准确性。应用该模型研究了直墙反射系数幅值及相位、方箱与墙间距离等参数对水面方箱上波浪激振力、附加质量和辐射阻尼的影响。结果表明:直墙反射系数幅值越大,波浪激振力、附加质量和辐射阻尼的波动越大,附加质量在一些频率下出现负值;相位角的变化会改变波浪激振力、附加质量和辐射阻尼曲线的偏移,在低频区对升沉附加质量有显著影响;方箱距离直墙越远,方箱上的波浪激振力、附加质量和辐射阻尼随波数振荡的频率越快,峰值频率向低频侧移动。Based on the image theory,the scattering problem of 2D objects in front of partially reflective vertical walls is equivalent to solving the scattering of the original object in open water and the linear superposition of the scattering from the image of the vertical wall.A numerical analysis model for the diffraction and radiation problems of arbitrary-shaped 2D objects in front of partially reflective vertical walls is established using a high-order boundary element method.The accuracy of the numerical model is validated through comparisons with published results of underwater rectangular boxes and submerged cylinders.The model is applied to investigate the impact of the reflection coefficient amplitude and phase,the distance between the box and the wall,on the wave-induced forces,added mass,and radiation damping on the water surface of the box.The results indicate that a larger amplitude of the reflection coefficient leads to greater fluctuations in wave exciting force,added mass,and radiation damping,with added mass becoming negative at certain frequencies.Changes in the phase angle alter the curves of wave forces,added mass,and radiation damping,significantly affecting the added mass in the low-frequency region.As the distance between the box and the vertical wall increases,the wave exciting force,added mass,and radiation damping on the box exhibit faster oscillations with wave numbers,and the peak frequency shifts towards the low-frequency side.

关 键 词：部分反射直墙 二维物体 波浪激振力 水动力系数 映像原理 边界元方法 

分 类 号：TV139.2[水利工程—水力学及河流动力学]