Wave-current interactions: an experimental and numerical study. Part 1. Linear waves

Abstract

The interaction between a regular wavetrain and an adverse current containing an arbitrary distribution of vorticity, in two dimensions, is studied using a linear theory. The model is used to predict the wavelength and the particle velocities under the waves and these are found to agree well with experimentally obtained data for a number of current profiles. Surprisingly accurate predictions, for the profiles considered, were also obtained from an irrotational wave–current model in which the constant current has a value equal to the depth-averaged mean of the measured current profile. The changes in the wave amplitude as the current magnitude increases are predicted using an irrotational slowly varying model with good agreement being found between theory and experiment.