The Generation of Internal Gravity Waves in a Multilayered Moving Fluid by a Flap-Type Wave Maker

Experiments have examined the waveforms generated by a flap-type wave maker in a moving, three-layer fluid. Results show that the observed modulating waveforms could be predicted accurately for low frequencies and that if the two interfaces are sufficiently close together, both mode-one waves (whose amplitude vary in the vertical such that there is only one maximum) and mode-two waves (with a vertical amplitude structure that contains two relative maxima) are generated of similar amplitude. This results in downstream shifts from sinuous to varicose modes of oscillation.