zbMATH — the first resource for mathematics

Resonantly interacting modes in wake-shear layers. (English) Zbl 0805.76019
The resonant interaction between the sinuous and varicose modes of a wake is studied for a family of velocity profiles with symmetry-breaking perturbations. The leading-order nonlinear interaction, which vanishes identically for symmetric wake profiles, increases dramatically as a small velocity ratio is imposed across the wake. Coefficients of the coupled amplitude equations describing the interaction in flows with asymmetric mean profiles are evaluated numerically for finite Reynolds numbers. The dynamical system defined by these equations is analyzed for temporally-forced, spatially-evolving modes for a velocity ratio where the flow is convectively unstable.
76E05 Parallel shear flows in hydrodynamic stability
76D25 Wakes and jets