Perturbation of transient forming vortex in pipe

Recently, we proposed what we call the self-induction mechanism of vortex breakdown by considering its transient formation. Out of this emerged two key ingredients necessary for the formation of the vortex breakdowns: 1) the vorticity gradient and 2) the initial straightness of the axisymmetric vortex. Here we apply the theory to consider whether we can control or suppress the vortex breakdown by perturbing the trajectory of the vortex from straight to kinky one. We have done computer simulation, based on vortex filament method. Initial result appears that, even the kink or perturbation introduces axial vorticity gradient, the axisymmetric vortex does not develop completely to vortex breakdown. The perturbed vortex simply disintegrates away. The result is compared with the available experimental work, which appears to agree. This lends support to the self-induction theory.