Mixed regular seas were first generated using multiple signal generators and summing their outputs. Since computers have been available they have been used for a wave synthesis using multiple wave fronts. Through this mechanism, both irregular seas with 3D wave effects have been generated. Initially, we were restricted to summing less than 100 fronts, but with the increase in computing power, we are now only limited by the repeat time of the wave.
The ability of current multiple wave front synthesizer to produce both special effects and fully randomized effects has been widely utilized. The tool has proved to be well suited for fundamental wave analysis, wave power machine testing, coastal engineering and ship dynamics testing. This tool is currently being used to generate 3D waves in at least 12 major tank facilities and almost 50 wave flumes. The capability of this tool has enabled extreme wave testing to be carried out for survival testing and for waves to be generated with wavemakers in any configuration. Fortuitously, these synthesis techniques have also allowed a wave show to be developed for use in a theme park.
With the extra requirements to synthesize waves in the wave basins at the Naval Surface Warfare Center, Carderock Division (NSWCCD), this proved an opportunity to review our wave synthesis capability in the light both of recent developments and user requirements. The development of an integrated tool with graphical display has allowed the exploration of a different techniques when generating wave effects in a wide variety of environments.
This flexibility has been further increased with the addition of the Dalrymple method and the ability to support a varying bottom topology. The power of modern graphics has not only allowed the wave to be displayed at a point as a plot against time, frequency and angular distribution but also as a full animation of the wave in the tank able to illustrate the impact of these effects.