DIFFRACTION OF WATER WAVES BY POROUS BREAKWATERS

Diffraction of water waves by porous breakwaters is studied based on the linear potential wave theory. The formulation of the problem includes a newly derived relation for the fluid motion through thin porous structures in addition to the conventional governing equation and boundary conditions for small-amplitude waves in ideal fluids. The porous boundary condition, indirectly verified by collected experimental data, is obtained by assuming that the flow within the porous medium is governed by a convection-neglected and porous- effect-modeled Euler equation. A vertically two-dimensional problem with long-crested waves propagating in the normal direction of an infinite porous wall is first solved and the solution is compared with available experimental data. The wave diffraction by a semiinfinite porous wall is then studied by the boundary-layer method, in which the outer approximation is formulated by virtue of the reduced two- dimensional solution. It is demonstrated that neglect of the inertial effect of the porous medium leads to an underestimate of the functional performance of a porous breakwater.

  • Supplemental Notes:
    • J Waterway, Port, Coastal, and Ocean Engng, v 121 n 6, Nov/Dec 1995, p 275 [8 p, 30 ref, 1 tab, 16 fig]
  • Authors:
    • Yu, Xiangzhan
  • Publication Date: 1995

Language

  • English

Subject/Index Terms

Filing Info

  • Accession Number: 00718524
  • Record Type: Publication
  • Source Agency: British Maritime Technology
  • Files: TRIS
  • Created Date: Mar 27 1996 12:00AM