孤立波作用于V形薄壁防波堤的绕射波浪力

Diffracted wave force on V-shaped thin wall breakwater caused by solitary wave

在一定条件下浅水波可能以孤立波形态作用于离岸结构。基于波浪绕射理论,推导V形薄壁防波堤的一阶孤立波绕射理论解。通过对孤立波作用于防波堤的波浪力进行计算,研究孤立波对V形防波堤的作用规律。通过对180°张角的有限长薄壁V形堤足够长时的绕射波浪力计算,与无限长直立薄壁堤的孤立波反射波浪力进行有效的相似性比较。结果表明:孤立波的最大无量纲波浪力明显大于相同浅水条件下Airy微幅波理论的对应结果,由此反映浅水波的非线性效应;孤立波入射角、V形堤张角、防波堤臂长与水深比以及孤立波特征参数等因素的变化均将对波浪荷载产生一定的影响。

In certain conditions,shallow water waves may emerge in solitary waveform,causing wave effects on offshore structures.Based on diffracted wave theory,we derive the theoretical solutions to first-order solitary water wave diffraction by a V-shaped thin wall breakwater,and study the action rule of a solitary wave on the breakwater by calculating solitary diffracted wave forces on the V-shaped breakwater.By calculating diffracted wave force on the finite length vertical thin-walled V-shaped breakwater with the opening angle 180°while the finite length breakwater is enough long,we carry out effectively similarity comparison with the reflected wave force caused by a solitary wave on the infinite long vertical thin-walled breakwater.The results show that the maximum dimensionless wave forces on the breakwater caused by solitary wave are obviously larger than those predicted by small-amplitude wave theory under Airy same shallow water conditions,reflecting the nonlinear effect of shallow water wave.The variation of incident wave angle,opening angle of V-shaped breakwater,the ratio of breakwater arm length and water depth,and solitary wave characteristic parameter may have some influence on wave loads.