EJ-SEVIER Coastal Engineering 28 ( 1996) 229-248 COASTAL zyxwvutsrqponm ENGINEERING 3-D non-breaking regular wave interaction with submerged breakwaters I.J. Losada *, R. Silva ‘, M.A. Imada Ocean & Coastal Research Group, Unioersidad de Cantabria, Dpto. de Ciencias y Ttknicas de1 Agua y de1 Media Ambiente. E.T.S.I. de Camitws, Canales y Puertos, Auda. de IOU Castros s/n., 39005 Santander, Spain Received 20 June 1995; accepted 5 April 19% zyxwvutsrqponmlkjihgfedcbaZYXWV Abstract Modelling of the transformation and interaction of regular wave trains with submerged permeable structures is carried out. The existing literature, is summarized relevant theories presented, and theoretical results are compared with existing laboratory data. Special attention is paid to wave reflection. The influence of wave characteristics including oblique incidence, structure geometry and porous material properties on the kinematics and dynamics over and inside the breakwater is considered. Two different models are presented: an eigenfunction expansion 3-D model and a 2-D model based on a mild-slope equation for porous media to account for breakwater slope. 1. Introduction Submerged breakwaters or sills have been constructed in coastal zones for shoreline or harbour protection or to prevent beach erosion. They can be built to reduce wave energy in their leeside by inducing wave breaking and dissipation due to friction. Perched beaches are designed using submerged sills which interrupt offshore sediment transport by providing a barrier to sediment transport whilst inducing the breaking of large waves only. * Corresponding author. Fax: 34-42-201860. Phone: 34-42-201810. e-mail: inigc@puerhpl.unican.es ’ Present address: lnstituto de Ingenieria, UNAM, Cd. Universitaria, Apdo. Postal 70-472, 045 10 Mexico, D.F., Mexico. 0378-3839/%/$15.00 Published by Elsevier Science B.V. PII SO378-3839(96)00019-l