Bragg Reflections of Oblique Water Waves by Periodic Surface-Piercing and Submerged Breakwaters

Journal of Marine Science and Engineering

Chia-Cheng Tsai¹  I-Fan Tseng¹  Chi-Shian You¹ 

[1] Department of Marine Environment and Engineering, National Sun Yat-sen University, Kaohsiung 80424, Taiwan;

关键词: eigenfunction matching method;    oblique wave;    Bragg reflection;    step approximation;    surface-piercing structure;    periodic bottom;   

DOI  :  10.3390/jmse8070522

来源: DOAJ

【 摘 要 】

The Bragg reflections of oblique water waves by periodic surface-piercing structures over periodic bottoms are investigated using the eigenfunction matching method (EMM). Based on the assumption of small wave amplitude, the linear wave theory is employed in the solution procedure. In the step approximation, the surface-piercing structures and the bottom profiles are sliced into shelves separated by abrupt steps. For each shelf, the solution is composed of eigenfunctions with unknown coefficients representing the wave amplitudes. Upon applying the conservations of mass and momentum, a system of linear equations is obtained and is then solved by a sparse-matrix solver. The proposed EMM is validated by several examples in the literature. Then, the method is applied to solve Bragg reflections of oblique water waves by various surface-piercing structures over periodic bottoms. From the numerical experiments, Bragg’s law of oblique waves was used to predict the occurrences of Bragg resonance.

【 授权许可】

Unknown