Nonlinear Characteristics of Internal Waves Propagating over a Submerged Breakwater

Abstract

Internal waves propagating over a submerged breakwater in a two-layer system are numerically simulated using a set of nonlinear internal-wave equations derived on the basis of a variational principle without any assumptions concerning wave nonlinearity and dispersion. When an internal-wave crest starts wave disintegration after passing over an offshore shoulder of submerged breakwater, both the horizontal velocity and dynamic pressure below the internal-wave crest show a remarkable distribution or a remarkable curvature of distribution in the vertical direction with wave dispersion. Over a submerged breakwater where the width of the breakwater crown is short or the lower-layer depth is deep over the breakwater crown, the crests of internal waves do not show wave disintegration.