Interaction of oblique water waves with a single chamber caisson type breakwater for a two-layer fluid flow over an elastic bottom

A finite ocean depth is considered with the bottom possessing elasticity and subsequently, the present investigation for an interface-piercing structure focusses on the influence of porous parameters of the structure on attenuation of waves in both surface and interfacial modes for a two-layer fluid flow. Further, the influence of the elastic bottom is studied by using the dispersion relation to analyze the flexural gravity wave motion with the influence of the flexural wave motion factored into the solution. The analytical results are graphically illustrated. Further, a different linear algebraic technique is adopted, and a comparison of the two methods supports our numerical finding. The reflection coefficients for waves in surface and interfacial modes is examined, along with their effects on the free surface and interface elevations and the wave-loads on the structure. Consequently, the appropriateness of various configurations of the structure on the scattering of surface waves is studied. As per the findings, an optimal width can be determined for a suitable configuration of the porous structure in order to build a breakwater with an acceptable performance of reflection and dissipation characteristics. Such an analysis is likely going to be immensely helpful for a variety of coastal systems in terms of reflection and dissipation of wave energy at continental shelves that is influenced by a stratified fluid, which is being sculptured during this work, as a two-layer fluid for a matter of convenience. The shear force and bottom deflection are discussed to examine how elastic parameters of the sea floor affect the scattering process. It also aids in the analysis of the transformation of physical properties of water waves as well as the structure's effectiveness. Analyzing the results with respect to the sea floor helps to reduce the waveload on the structure which consequently protects the shore. The analytical solution approximation findings are consistent with previous results from theoretical methods with an impermeable bottom. This research presents a basic and elegant method for dealing with water wave encountering submerged porous structures, and these results can be used as a reliable substitute technique for preliminary engineering analysis. Additionally, an identical geometrical structure is also considered which contains a perforated front wall. Comparison of results for those two completely different structures points towards an additional effectiveness of the model.