PRIMARY INSTABILITIES IN FARADAY WAVES UNDER AN ARBITRARILY PERIODIC EXCITATION

Under a vertically arbitrarily periodic excitation, the primary Farada y instability of the flat surface of a viscous fluid layer has been an alyzed by the linear stability theory. As an application, the pattern instabilities induced by the two-frequency forcing have been calculate d numerically according to the known experiments. The theoretical marg inal instability curves as well as the bicriticality threshold curves are in good agreement with those measured in recent experiments.