Experimental study of Stokes drift in combined wave-current flows using Particle Image Velocimetry

Abstract

Abstract In the present study, Eulerian velocities were obtained using the PIV system to investigate the problem of Stokes drift in combined wave-current flows. Time-averaged mean Eulerian velocity profiles were presented after the flow has achieved its equilibrium status. Waves with various wave periods and amplitudes were generated and propagated with the turbulent current possessing a Reynolds number of 32000. Results of the time-averaged mean velocity profiles suggest the absence of a return flow in an open flume. The discrepancies of the depth-averaged mean velocity with and without waves superimposed were found to be in good agreements with the return flow speeds as predicted by Kim (1984). This further confirmed the applicability of their solution for calculating the return flow under the condition of waves propagating with currents.