摘要
Dynamo theory describes the magnetic field induced by the rotating,convecting and electrically conducting fluid in a celestial body.The classical ABC-flow model represents fast dynamo action,required to sustain such a magnetic field.In this letter,Lagrangian coherent structures(LCSs)in the ABC-flow are detected through Finite-time Lyapunov exponents(FTLE).The flow skeleton is identified by extracting intersections between repelling and attracting LCSs.For the case A=B=C=1,the skeleton structures are made up from lines connecting two different types of stagnation points in the ABC-flow.The corresponding kinematic ABC-dynamo problem is solved using a spectral method,and the distribution of cigar-like magnetic structures visualized.Inherent links are found to exist between LCSs in the ABC-flow and induced magnetic structures,which provides insight into the mechanism behind the ABC-dynamo.
基金
supported by the National Natural Science Foundation of China(Grant No.51979162)。
作者简介
Corresponding author:ZhiLiang Lin,email:linzhiliang@sjtu.edu.cn。
