Magneto-Rayleigh–Taylor instability in an elastic finite-width medium overlying an ideal fluid
Magneto-Rayleigh–Taylor instability in an elastic finite-width medium overlying an ideal fluid
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DOI：
10.1017/jfm.2019.193
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发表时间：
2019-03
影响因子：
3.7
通讯作者：
S. Piriz;A. R. Piriz;N. Tahir
中科院分区：
文献类型：
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作者：
S. Piriz;A. R. Piriz;N. Tahir
我们提出了二维不可压缩磁瑞利-泰勒不稳定性的线性理论，该系统由较轻的半无限理想流体上方的线弹性（胡克）层组成，层上方和下方均存在磁场。正如预期的那样，磁场效应和弹性效应共同增强了厚层的稳定性。然而，对于相对较薄的板坯，情况变得更加复杂，并且观察到许多新的和意想不到的现象。特别是，当该层下方的磁场占主导地位时，其效应与弹性效应相竞争，并抵消弹性的稳定效应。因此，与仅其中一种稳定机制起作用时相比，该层可能变得更加不稳定。这种有点出乎意料的结果可以通过弹性和磁场稳定系统的不同物理机制来解释。讨论了磁驱动加速板和内爆实验的意义。此外，还指出了强磁化中子星触发地壳地震的相关性。
We present the linear theory of two-dimensional incompressible magneto-Rayleigh–Taylor instability in a system composed of a linear elastic (Hookean) layer above a lighter semi-infinite ideal fluid with magnetic fields present, above and below the layer. As expected, magnetic field effects and elasticity effects together enhance the stability of thick layers. However, the situation becomes more complicated for relatively thin slabs, and a number of new and unexpected phenomena are observed. In particular, when the magnetic field beneath the layer dominates, its effects compete with effects due to elasticity, and counteract the stabilising effects of the elasticity. As a consequence, the layer can become more unstable than when only one of these stabilising mechanisms is acting. This somewhat unexpected result is explained by the different physical mechanisms for which elasticity and magnetic fields stabilise the system. Implications for experiments on magnetically driven accelerated plates and implosions are discussed. Moreover, the relevance for triggering of crust-quakes in strongly magnetised neutron stars is also pointed out.