H. Behera

Oblique Wave Trapping by Porous Structures Near a Wall

AbstractThe current study deals with the oblique wave trapping by bottom-standing and surface-piercing porous structures of finite width placed at a finite distance from a vertical rigid wall. Using the Sollitt and Cross model for wave motion within the porous structure, the problems are analyzed based on the small-amplitude water wave theory in water of finite depth. The solutions of the associated boundary value problems are obtained analytically using the eigenfunction expansion method and numerically using a multidomain boundary-element method. In the boundary-element method, the boundary value problems are converted into integral equations over the physical boundaries. The physical boundaries are discretized into a finite number of elements to obtain a system of linear algebraic equations. Various aspects of structural configurations, in trapping surface gravity waves, are analyzed from the computed results on the reflection coefficients and the hydrodynamic forces. Suitable arrangements of the rigid...

Oblique wave trapping by porous and flexible structures in a two-layer fluid

Trapping of obliquely incident surface waves by permeable flexible barriers placed near a vertical rigid wall in a two-layer fluid having free surface and an interface is studied for both surface-piercing and bottom-standing partial barriers. For the surface-piercing permeable flexible barrier, the barrier is assumed to be fixed near the free surface and is free at the submerged end. On the other hand, for the bottom standing permeable flexible barrier, the barrier is assumed to be fixed at the bottom and the other end is free. As special cases of the permeable flexible barrier, the results associated with surface-piercing and bottom-standing permeable membrane barriers are obtained by assuming that the two ends of the barriers are fixed. Appropriate continuity conditions are used to deal with the interface-piercing flexible/membrane barriers. The mathematical problem is handled for solution using a generalized orthogonal relation suitable for two-layer fluid along with the least square approximation meth...

Oblique wave scattering by double porous structures

The linear wave scattering by double submerged structures of different structural parameters in oblique sea is investigated by use of eigenfunction expansion method. The important hydrodynamical scattering quantities such as reflection, transmission and dissipation coefficients are obtained and analyzed to examine the effects of various wave and structural parameters. As a special case, the computational results are validated for their accuracy by comparing with known results in the literature in case of single structure. The study reveals that a significant amount of wave energy dissipated in case of double structures as compared to that in the presence of single structure. Moreover, the energy dissipation is found to be independent of relative spacing between the two structures.