The Rotating Rayleigh-Taylor Instability

Matthew M. Scase; Kyle A. Baldwin; Richard J. A. Hill

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arXiv · 1603.00675

The Rotating Rayleigh-Taylor Instability

Matthew M. Scase·Kyle A. Baldwin·Richard J. A. Hill

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Abstract

The effect of rotation upon the classical two-layer Rayleigh-Taylor instability is considered theoretically and compared with previous experimental results. In particular we consider a two-layer system with an axis of rotation that is perpendicular to the interface between the layers. In general we find that a wave mode's growth rate may be reduced by rotation. We further show that in some cases, unstable axisymmetric wave modes may be stabilized by rotating the system above a critical rotation rate associated with the mode's wavelength, the Atwood number and the flow's aspect ratio. We compare our theory with experiments conducted in a magnetic field using 'heavy' diamagnetic and 'light' paramagnetic fluids and present comparisons between the theoretical predictions and experimental observations.

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Matthew M. Scase, Kyle A. Baldwin, Richard J. A. Hill. 2016-03-02. The Rotating Rayleigh-Taylor Instability. https://arxiv.org/abs/1603.00675

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