Rotating helical turbulence. II. Intermittencyscale invarianceand structures

We study the intermittency properties of the energy and helicity cascades in two 15363 direct numerical simulations of helical rotating turbulence. Symmetric and antisymmetric velocity increments are examinedas well as probability density functions of the velocity field and of the helicity density....

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Detalles Bibliográficos
Autores: Mininni, P.D., Pouquet, A.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Institución:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
Repositorio:Biblioteca Digital (UBA-FCEN)
Idioma:inglés
OAI Identifier:paperaa:paper_10706631_v22_n3_p6_Mininni
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_10706631_v22_n3_p6_Mininni
Access Level:acceso abierto
Palabra clave:Anti-symmetric
Different order
Helical turbulence
Helicities
Helicity cascades
Intermittency
Rotating turbulence
Scale invariant
Self-similarities
Small scale
Structure functions
Time-varying vortices
Velocity field
Velocity increments
Computer simulation
Rotation
Turbulence
Probability density function
Descripción
Sumario:We study the intermittency properties of the energy and helicity cascades in two 15363 direct numerical simulations of helical rotating turbulence. Symmetric and antisymmetric velocity increments are examinedas well as probability density functions of the velocity field and of the helicity density. It is found that the direct cascade of energy to small scales is scale invariant and nonintermittentwhereas the direct cascade of helicity is highly intermittent. Furthermorethe study of structure functions of different orders allows us to identify a recovery of isotropy of strong events at very small scales in the flow. Finallywe observe the juxtaposition in space of strong laminar and persistent helical columns next to time-varying vortex tanglesthe former being associated with the self-similarity of energy and the latter with the intermittency of helicity. © 2010 American Institute of Physics.