Axisymmetric internal wave tunneling
Résumé
Though internal waves cannot propagate vertically through weakly stratified fluid, if the depth of the weak stratification is sufficiently shallow, these waves can partially reflect from and transmit through it. In this paper, we quantitatively extend the results of Sutherland and Yewchuk on Cartesian internal wave tunneling to the case of axisymmetric wave fields and discuss their tunneling through a weakly stratified layer. A simple three-layer model allowing for the computation of transmission coefficients for the velocity fields is proposed and tested on a case study. We notably show that there exists a smooth transition between the fully propagating and the tunneling regimes. We further reflect on the challenges set by the measurement of internal wave modes amplitudes in confined domains, and we discuss an innovative method to measure said amplitudes in this experimental and numerical context.