Dynamo action in simple convective flows
Dynamo action in simple convective flows
复制标题
简单对流中的发电机作用
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
Paul C. Matthews
中科院分区：
文献类型：
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作者：
Paul C. Matthews
Several simple steady flows generated by thermal convection are investigated, to determine which of them are able to generate a magnetic field through dynamo action. For steady convection in a non–rotating layer of fluid in the form of a square or hexagonal pattern, no dynamo action is found. However, spurious dynamo action can easily be obtained if the numerical resolution used is inadequate. Such erroneous results occur both with a fully spectral method and with a mixed pseudo–spectral and finite–difference method. For convection in a rotating layer, it is found that even the simplest form of convection, two–dimensional rolls, can act as a dynamo, provided that the nonlinearity of the flow is taken into account. The dynamo operates most efficiently for moderate values of the rotation rate and fails in the rapidly rotating limit. In the nonlinear regime a branch of steady equilibrated dynamos is found, but dynamo action ceases when the thermal forcing becomes sufficiently strong.
