Laboratory Simulation of Sea Waves

An investigation was undertaken to discover the extent to which statistical properties of wind-generated waves can be simulated on a small scale under laboratory conditions. Experimental data were collected in a wind and wave facility for more than 150 sea conditions at twelve fetches (9 ft to 65 ft) and ten wind speeds (19 fps to 72 fps). Continuous water surface elevation recordings, as sensed by capacitance wire transducers and recorded in analog form on magnetic tape, were digitized for analysis by computer. The wave energy spectra exhibit properties which are at least qualitatively similar to those obtained under oceanic conditions. Moreover, the data substantiate the analysis by Longuet-Higgins in which the wave heights are described by a Rayleigh probability distribution. Comparison of laboratory and field data demonstrates that statistical parameters derived on the basis of Longuet-Higgins' theoretical results are in good agreement over a large range of sea wave environments.