On the Modified Truncated Wave Spectra for the Artificial IrregularWater Wave Generation

Any wave generator of model basins has always a limitation of generating capability concerning with both wave frequency and amplitude. So, it is only practically possible in tanks to generate a truncated spectra waves in some frequency range.Meanwhile, the model experiments in irregular waves to keep the specific values of H and T are oftenly demanded by customers. In these cases, the realization of specific H and T should have priority over the realization of spectra shapes.Therefore, we introduce the “Modified Truncated Wave Spectra” to keep the specified values of T and H, and the following items are investigated in this paper.1) Calculating methods on the modified truncated spectra are induced for P-M type and JONSWAP type.2) Practical usefulness of these spectra is checked by the experiments.