Magnetic field generation by pointwise zero-helicity three-dimensional steady flow of an incompressible electrically conducting fluid

• Type: Article in International Scientific Journal
• Date: 2018

Authors

A. Rasskazov (Author) Other; R. Chertovskih (Author) FEUP; V. Zheligovsky (Author) Other

Journal

Title: Physical review. E

Vol. 97 No. 4

Pages: 1-37

ISSN: 2470-0045

Publisher: American Physical Society

Indexing

ISI Web of Knowledge - 12 Citations

Scopus - 11 Citations

INSPEC

Other information

Authenticus ID: P-00N-V6K

DOI: 10.1103/physreve.97.043201

Abstract (EN): We introduce six families of three-dimensional space-periodic steady solenoidal flows, whose kinetic helicity density is zero at any point. Four families are analytically defined. Flows in four families have zero helicity spectrum. Sample flows from five families are used to demonstrate numerically that neither zero kinetic helicity density nor zero helicity spectrum prohibit generation of large-scale magnetic field by the two most prominent dynamo mechanisms: the magnetic alpha-effect and negative eddy diffusivity. Our computations also attest that such flows often generate small-scale field for sufficiently small magnetic molecular diffusivity. These findings indicate that kinetic helicity and helicity spectrum are not the quantities controlling the dynamo properties of a flow regardless of whether scale separation is present or not.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 37