AN EFFICIENT METHOD FOR THE REPRODUCTION OF NON-LINEAR RANDOM WAVES

Abstract

For the laboratory study of many random-wave induced phenomena, wave-board control signals according to linear wave theory are not sufficient: apart from bound suband superharmonic waves, spurious free waves are generated. Wave generation according to a higher-order wave theory is necessary in order to suppress these spurious waves. The perturbation method of multiple scales is used to derive formulas for the secondorder wave-board control signal, assuming the carrier-wave spectrum is narrow banded. The resulting algorithm is much faster than the one based on the full second-order theory. Furthermore, the applicability of the narrow-band approximation is indicated for carrier-wave spectra frequently used in coastal and ocean engineering.