A mathematical model of uniform longshore currents and the comparison with laboratory data

A mathematical model of uniform longshore currents and the comparison with laboratory data

Visser, P.J.

Civil Engineering and Geosciences

Hydraulic Engineering

1984-01-01

This report describes a mathematical model for uniform longshore currents and laboratory experiments on these currents, as also the comparison of theory and experiment. The longshore driving force is modeled taking into account the physical fact that dissipation of wave energy takes place shoreward of the plunge instead of in the whole surf zone as usely assumed. The bottom friction is modeled by considering the combined orbital and mean current velocity vector. This is done in several manners since it is still unclear how to combine these velocities near the bqttom. The lateral friction is modeled according to Battjes (1975, 1983). The data obtained from the present longshore current experiments appear to be very usable to verify the theoretical results: the rate of accuracy of the measurement results is high, the longshore current profiles are uniform and these were measured in detail. The experimental results do not confirm the often made assumption of a logarithmic vertical velocity profile. The agreement between the longshore currents predicted by the mathematical model and the experiments is good and this has been achieved with realistic values of the bottom roughness.

longshore current
beach hydrodynamics
radiation stress

http://resolver.tudelft.nl/uuid:648ad326-4c44-4646-ab73-559a118a8ab4

TU Delft

01696548

Communications on hydraulic engineering, No. 1984-2

Institutional Repository

report

(c) 1984 Visser, P.J.