Faraday waves: their dispersion relation, nature of bifurcation and wavenumber selection revisited

International audienceIn the current literature, the dispersion relation of parametrically-forced surface waves is often identified with that of free unforced waves. We revisit here the theoretical description of Faraday waves, showing that forcing and dissipation play a significant role in the dispersion relation, rendering it bi-valued. We then determine the instability thresholds and the wavenumber selection in cases of both short and long waves. We show that the bifurcation can be either supercritical or subcritical, depending on the depth