Chaos, Solitons & Fractals ( IF 5.3 ) Pub Date : 2021-01-21 , DOI: 10.1016/j.chaos.2020.110600 Hiya Mondal , Alaka Das , Krishna Kumar
Two low-dimensional models for nonlinear dynamo action in Rayleigh-Bénard convection in presence of rigid body rotation about vertical axis are constructed for metallic fluids with finite magnetic Prandtl number () and small (or zero) thermal Prandtl number (). Dynamo effect is seen for with and Taylor number, . The value of reduced Rayleigh number at the dynamo onset () varies with and . The value of decreases with increase in and separately, if the other two parameters are kept fixed to some small values. However increases slightly if is increased, the value being minimum for . When dynamo onset appears as intermittent chaotic burst. The intermittent burst changes to continuous chaos with rise in . The probability mass of the height of peak in average magnetic energy follows power law when is small. For and dynamo effect starts at the onset of convection as finite oscillation. This effect continues in a small window of and then disappears. The dynamo action again appears as quasi-periodic wave or chaotic wave for further increase in .
中文翻译:
旋转磁对流中发电机作用的低维模型
针对具有有限磁Prandtl数的金属流体,建立了两个存在于低速运动中的二维模型,这些模型用于在瑞利-贝纳德对流中存在绕垂直轴旋转的刚体的情况下的非线性发电机作用。)和较小(或为零)的热普朗特数()。可以看到发电机效果 与 和泰勒数, 。发电机开始时瑞利数减少的值()随 和 。的价值 随着增加而减少 和 如果其他两个参数保持固定为一些小值,则分别。然而 如果稍微增加 增加,该值是 。什么时候发电机的发作表现为间歇性的混沌爆发。间歇性脉冲随着上升而变成连续的混乱。平均磁能中峰高的概率质量遵循幂定律是小。对于 和 发电机效应在对流开始时作为有限振荡而开始。这种效果会在然后消失。发电机动作再次以准周期波或混沌波出现,以进一步增加。