Measurement of Mean Flows in Faraday Waves

We measure the velocities of the mean flows which are driven by curved rolls in a pattern formation system. Curved rolls in Faraday waves are generated in experimental cells consisting of channels with varying widths. The mean flow magnitudes are found to scale linearly with roll curvatures and squares of wave amplitudes, agreeing with prediction from the analysis of phase dynamics expansion. The effects of the mean flows on reducing roll curvatures are also seen.