Response of the axisymmetric mixing layer to subharmonic forcing at different amplitudes.

An initially laminar axisymmetric mixing layer of a large air jet was subjected to high-amplitude forcing at a subharmonic of the natural instability frequency. The excitation was induced acoustically through an axisymmetric slit at the lip without inducing bulk excitation of the jet exit flow. Various subharmonics were tested. (T.R.A.)