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

• Tipo: Artigo em Revista Científica Internacional
• Data: 2018

Autores

A. Rasskazov (Autor) Outra; R. Chertovskih (Autor) FEUP; V. Zheligovsky (Autor) Outra

Revista

Título: Physical review. E

Vol. 97 Nº 4

Páginas: 1-37

ISSN: 2470-0045

Editora: American Physical Society

Indexação

ISI Web of Knowledge - 12 Citações

Scopus - 11 Citações

INSPEC

Outras Informações

ID Authenticus: 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.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 37