Bragg resonance of membrane-coupled gravity waves over a porous bottom
Tóm tắt
A second order mild-slope model equation is proposed to study scattering of membrane-coupled gravity waves by floating membrane and porous bottom variations. Periodic geometric variations are considered either in the floating membrane or in the porous bottom. The depth averaged equation is derived by means of Green’s second identity. Mass conserving jump conditions are extracted and applied at possible slope discontinuities in the floating membrane or porous bottom. The two-dimensional equation is solved numerically and Bragg resonance is investigated for periodic variations like protrusions, indentations and sinusoidal. Reflection is found to be significant for specific membrane variations. Numerical accuracy in the reflection has been verified through the energy balance relation. Also, it is found that varying porous bottoms provide better reflection characteristics.
Tài liệu tham khảo
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