Citation

Wind HG, Vreugdenhil CB. Journal of Fluid Mechanics 1986; 171(-1): 459.

Copyright

(Copyright © 1986, Cambridge University Press)

DOI

10.1017/S0022112086001520

PMID

unavailable

Abstract

Data have been obtained for a wave-driven current system in a closed basin. Owing to interaction of the longshore current with the sidewall a strong rip current was generated. The velocity distribution over the depth of the rip current appeared to be more or less uniform. The current system has been modelled by means of a mathematical model. The effect of bottom topography, bottom friction, convection and turbulent viscosity on the current system has been investigated. The conclusions are that the rip current is dominated by convection and that the bottom topography plays a role in the convergence and divergence of the streamlines. The order of magnitude of the velocities is largely determined by the bottom-friction coefficient. The velocity field is modified by viscosity. First, turbulent viscosity entrains fluid in the longshore current and into the rip current, secondly it permits turbulent boundary layers and thirdly it is responsible for the existence of closed streamlines outside the breaker zone. Finally the model and the conclusions are extrapolated to prototype conditions.

Keywords: Drowning; Drowning Prevention; Water Safety