Suppression of Rayleigh–Taylor instability by flow curvature

The question of whether it is the shear [V(r)′] or the curvature [V(r)″] in the flow profile [V(r)] which plays the dominant role in suppressing the low-frequency (ω<ωi, where ωi is the ion gyrofrequency) instabilities and fluctuations is investigated. Rayleigh–Taylor (RT) instability is considered in this work. The role of flow curvature is found to have a robust effect on the stability and on the radial structure of the mode. For a positive value in the flow curvature RT is suppressed whereas a negative flow curvature excites the mode. Flow shear, on the other hand, plays an insignificant role in this matter. These theoretical findings are in agreement with the recent experimental results.