SPECTRAL CHARACTERISTICS OF WIND-WAVES IN LABORATORY

Spectral characteristics of wind-generated waves in labortaory are pre sented on the basis of a systematic measurement in a large-scale wind- wave channel and compared with those in the field. A marked characteri stics of the measured spetra is the existence of secondary spectrum-pe ak. The dependence of spectral peak-frequency, peak-value and zeroth-o rder moment on wind speed and fetch are presented and found roughly si milar to those in the field represented by the JONSWAP spectrum, regar dless of the differences in coefficient. The spectral slope beta at hi gh-frequencies are found somewhat greater than those of field wind-wav es in both cases of deep and shallow waters. Except for the low-freque ncy part, the spectral forms measured in different wind conditions are similar and fit for the JONSWAP spectrum with gamma = 6 and beta = 5. 5. Some relevant problems are discussed.