in a laboratory wave flume , with a length of 307 m and a depth of 7 m. A
wave flume (or
wave channel) is a special sort of wave tank: the width of the
flume is much less than its length. The generated waves are therefore – more or less –
two-dimensional in a vertical plane (2DV), meaning that the orbital
flow velocity component in the direction
perpendicular to the flume side wall is much smaller than the other two components of the
three-dimensional velocity
vector. This makes a wave flume a well-suited facility to study near-2DV structures, like cross-sections of a
breakwater. Also (3D) constructions providing little blockage to the flow may be tested, e.g. measuring wave forces on vertical cylinders with a diameter much less than the flume width. Wave flumes may be used to study the effects of
water waves on
coastal structures,
offshore structures,
sediment transport and other
transport phenomena. The waves are most often generated with a mechanical wavemaker, although there are also wind–wave flumes with (additional) wave generation by an air flow over the water – with the flume closed above by a roof above the free surface. The wavemaker frequently consists of a translating or rotating rigid wave board. Modern wavemakers are computer controlled, and can generate besides
periodic waves also
random waves,
solitary waves,
wave groups or even
tsunami-like wave motion. The wavemaker is at one end of the wave flume, and at the other end is the construction being tested, or a wave absorber (a beach or special wave absorbing constructions). Often, the side walls contain glass windows, or are completely made of glass, allowing for a clear visual observation of the experiment, and the easy deployment of optical instruments (e.g. by
Laser Doppler velocimetry or
particle image velocimetry). == Circular wave basin ==