In the near future, the wavemaking facilities at the Naval Surface Warfare Center, Carderock Division (NSWCCD) will be equipped with actively absorbing, force-feedback controlled wavemakers. The purpose of the present study is to demonstrate the successful application of a novel theoretical transfer function appropriate to the operation of such wave machines. This transfer function has been formulated in an earlier study by the same authors and models the wave machine as a coupled hydrodynamic system.
In modelling the wave machine’s dynamic behaviour, the hydrodynamic coefficients are accounted for in an analytical fashion; such an approach being supported by the relatively simple geometries of the most common wave boards. Given the resulting theoretical transfer function, which directly relates the force demand signal to the wave field in the tank, the latter may be evaluated before the experiment. Coupled with a pseudo-random wave generation or synthesis technique, the theoretical model enables the numerical prediction of the surface profile in the facility.
With the relevant theory having being established, the experimental data presented herein is complementary to the earlier work. In particular, the simultaneous generation and absorption in a double ended wave flume is discussed. This includes both the generation of regular wave trains as well as irregular or random seas. The work presented herein is limited to the generation and absorption of uni-directional waves in wave flumes. However, the theoretical and practical aspects of multi-directional wave generation in force control have now been formulated and reference to this separate study is made.
