Gravity waves interacting with a narrow jet-like current.
J GEOPHYS RES-OCEANS
, Article C03009. 10.1029/2005JC003030.
 A unique experiment to investigate the transformation of near-linear gravity waves propagating across a narrow horizontally sheared jet-like current, typical of those found in the nearshore, coastal, and ocean regions, is described. A single wave condition was studied, propagating across the current orthogonally and at oblique incidence in both a following and opposing sense to the current. The length scale of the current shear layers was comparable to the incident wavelength. The experiment is the first attempt to assess the kinematics and dynamics of the interaction of regular waves and currents in three dimensions at a physically realistic scale. The resulting data set provides direct quantitative measurements of the spatial variation of the primary flow variables. Negligible reflection of the incident wave at the current shear layers was observed. Typical refraction behavior was observed: A following wave is refracted to a more current-parallel direction with an increased wavelength and reduced wave height as it moves onto the current, while the opposing wave becomes more current normal with a shortened wavelength and enhanced wave height. The experimental data are compared with predictions of a wave ray model, assuming a depth-averaged current and slowly varying horizontal shear, and a new model that incorporates the influence of vertical shear.
|Title:||Gravity waves interacting with a narrow jet-like current|
|Keywords:||DEEP-WATER WAVES, TURBULENT CURRENT, SHEARING CURRENT, SHALLOW-WATER, PROPAGATION, REFLECTION|
|UCL classification:||UCL > School of BEAMS
UCL > School of BEAMS > Faculty of Engineering Science
Archive Staff Only