The role of wave breaking on the development of wave spectra and bispectra in the surf zone

Abstract

Many countries around the world have a coastal area, which provides them with numerous benefits. To protect this first line of defense, it is relevant to have knowledge about the influence of breaking waves on the development of wave spectra and bispectra in the surf zone. This largely determines whether a coast erodes or accretes. Three contradicting theories about the relation between relative dissipation and frequency exist. The objective of this paper is to carry out some real-scale flume experiments that study the behaviour of waves in the surf zone. In the flume a barrier was placed where waves were breaking significantly. Three cases with different wave and water level properties were performed in order to research the differences. The results are that dissipation does not occur in the lower frequency range (0-0.2 Hz), but only in the higher frequency range (0.2 -0.4 Hz). For this higher frequency range a horizontal relation between relative dissipation and frequency is found, but more research about this is needed.