Experimental generation of axisymmetric internal wave super-harmonics

In this paper, we present an experimental study of weakly non-linear interaction axisymmetric internal gravity waves in a resonant cavity, supported by theoretical considerations. Contrary to plane Cartesian coordinates, for which self-interacting terms are null linear stratifiation, the self-interaction wave mode geometry is found be efficient at producing super-harmonics, i.e. whose frequencies integer multiples excitation frequency. Due range tested our experiments, first harmonic frequency below cut-off imposed stratification so lowest created can always propagate. The shows that super-harmonic field sum standing satisfying both dispersion relation and boundary conditions cavity walls, while conserving axisymmetry.