Azimuthal mode interaction in counter-rotating Taylor-Couette flow

The stability of flows near two critical points (in parameter space) at which Couette flow looses stability simultaneously to two non-axisymmetric wavenumbers has been studied experimentally. The findings are compared with the theoretical predictions of [Chossat et al., 1987], hereafter cited as CDI. In the case of the first critical point, resulting from the interaction of azimuthal wavenumbers m = 1 and m = 2, some quantitative disagreements with predictions were observed. The second point, resulting from the interaction between m = 2 and m = 3, was found at a slightly different location than that predicted by the theory. A transition to a seemingly chaotic regime was observed in addition to the transitions predicted by CDI. Experiments also show a nonperiodic amplitude variation of the velocity signal and a first transition to a doubly-periodic flow.