IFIBA   22255
INSTITUTO DE FISICA DE BUENOS AIRES
Unidad Ejecutora - UE
artículos
Título:
Spectral modeling of rotating turbulent flows
Autor/es:
J. BAERENZUNG; P.D. MININNI; A. POUQUET; H. POLITANO; Y. PONTY
Revista:
PHYSICS OF FLUIDS
Editorial:
AMER INST PHYSICS
Referencias:
Año: 2010 vol. 22 p. 251041 - 2510413
ISSN:
1070-6631
Resumen:
A subgrid-scale spectral model of rotating turbulent flows is tested
against direct numerical simulations (DNSs). The case of TaylorGreen
forcing is considered, a configuration that mimics the flow between two
counter-rotating disks as often used in the laboratory. Computations
are performed for moderate rotation down to Rossby numbers of 0.03, as
can be encountered in the Earths atmosphere. We provide several
measures of the degree of anisotropy of the small scales and conclude
that an isotropic model may suffice at moderate Rossby number. The
model, developed previously [
J. Baerenzung, H. Politano, Y. Ponty, and A. Pouquet, Spectral
modeling of turbulent flows and the role of helicity, Phys. Rev. E 77,
046303 (2008)
], incorporates eddy viscosity and eddy noise that depend
dynamically on the index of the energy spectrum. We show that the model
reproduces satisfactorily all large-scale properties of the DNS up to
Reynolds numbers of ∼ 104
and for long times after the onset of the inverse cascade of energy; it
is also shown to behave better than either the CholletLesieur eddy
viscosity model [
J. P. Chollet and M. Lesieur, Parametrization of small scales of
three-dimensional isotropic turbulence utilizing spectral closures, J.
Atmos. Sci. 38, 2747 (1981)
] or an under-resolved DNS.