Discussion: some results from wave pulse experiments

Abstract

Figures 1 to 3 represent a condensed account of some wave pulse experiments carried out in a long tank equipped with a wavemaker. The object of the experiments was to observe the effects of finite amplitude on the shape and frequency distribution of wave pulses propagated on deep water. Each pulse was generated by varying the wavemaker stroke smoothly from an amplitude of zero to some maximum value and back down to zero again. The resulting surface displacement was then recorded electrically at various positions along the centreline of the wave tank. The wavemaker frequency was 2·5 c/s throughout (corresponding to a regular wavelength of about 10in.). The pulse periods, which were selected to represent rapid and slow rates of modulation, were 12½ and 25 wavemaker periods.