V形布局起伏地形上布拉格共振引起的波能聚焦特性研究

The focusing characteristics of wave energy caused by Bragg resonance on V-shaped bottom

基于高阶谱(HOS)方法,文章建立了考虑起伏地形上三维布拉格共振的数值模型。基于该模型探讨了地形为V形空间布局时的波能聚焦特性,对比分析了地形不同夹角(α)下波能聚焦点处的聚焦效果。试验结果表明:V形布局中不同的α有着不同的聚波特性,通过优化α,可以很大程度上提高波能聚焦效果;当145°<α<180°时,波能聚焦效果较好,波能聚焦点处的振幅可达到初始入射波振幅的1.70倍以上,其中α=162.24°时,波能聚焦效果最优,最大振幅增大2.87倍。

Based on the high-order spectral(HOS) method, a three-dimensional Bragg resonance model considering the effects of undulating bottom is established. Based on this model, the wave energy focusing characteristics of V-shaped bottom are discussed, and the wave energy focusing effect at the wave energy focusing points of different bottom angles is compared and analyzed. The experimental results show that different angles α of V-shaped layout bottom have different wave focusing effects. By optimizing the angle of V-shaped bottom, the wave energy focusing effect can be greatly improved. When 145 ° <α <180 °, the wave energy focusing effect is better. The wave amplitude at the wave energy focusing points can reach more than 1.70 times of that of the initial incident waves. When α=162.24 °, the focusing effect of wave energy is the best, and the maximum amplitude increases by 2.87 times.