Results 211 to 220 of about 15,562 (263)

Turbulence Transport Equations

The Physics of Fluids, 1967
A generalized eddy viscosity function σ, is introduced in order that the Reynolds stress in an incompressible fluid be expressible as a linear combination of the Kronecker and rate-of-strain tensors. A transport equation for the eddy viscosity is derived from the general turbulence energy equation, thereby introducing two additional functions, the ...
Harlow, F. H., Nakayama, P. I.
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Barriers for Transport in Turbulent Plasmas

Physical Review Letters, 2003
The control of transport due to electrostatic turbulence is investigated using test-particle simulations. We show that a barrier for the transport, that is, a region where transport is reduced, can be generated through the randomization of phases of the turbulent field.
CARBONE, Vincenzo, LEPRETI, Fabio, VELTRI, Pierluigi   +2 more
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On the turbulent transport of a passive scalar by anisotropic turbulence

Physics of Fluids, 1996
The effect of anisotropic turbulence on the vertical transport of a tracer in a fluid layer is investigated numerically. It is found that for a fixed vertical turbulence spectrum an increase in the intensity of horizontal turbulence reduces the efficiency of the vertical transport.
Vincent, A., Michaud, G., Meneguzzi, M.
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Turbulent Transport in Stellar Interiors

Theoretical and Computational Fluid Dynamics, 1998
The authors consider differential rotation as a major cause of turbulence in stably stratified stellar interiors. It is shown that for an anisotropy \(A\) of horizontal to vertical velocities, the vertical diffusivity is a factor \(A^2\) less than the horizontal diffusivity. Transport by meridional circulation is also reduced, as well as the efficiency
Michaud, G., Zahn, J.-P.
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Turbulent Particle Transport in Magnetized Plasmas

Physical Review Letters, 2003
Particle transport in magnetized plasmas is investigated with a fluid model of drift wave turbulence. An analytical calculation shows that magnetic field curvature and thermodiffusion drive an anomalous pinch. The curvature driven pinch velocity is consistent with the prediction of turbulence equipartition theory.
Garbet X, Garzotti L, Mantica P, Nordman H, Valovic M, Weisen H, Angioni C   +6 more
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Turbulent Impurity Transport

AIP Conference Proceedings, 2008
Impurity transport is an important topic for ITER as impurity density in the core has to stay below a relative concentration of 5×10−5 [1] to reach ignition conditions. The reasons for that is mainly impurity radiation leading to cooling. In the edge region on the other hand site, higher impurity densities, going along with radiation energy losses are ...
Volker Naulin, Jens Juul Rasmussen, Clemente Angioni, Carine Giroud, Marco Valisa, Maria Ester Puiatti, L. Carraro, Sadruddin Benkadda   +7 more
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Nondeterministic Dynamics and Turbulent Transport

Annales Henri Poincaré, 2003
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Transport Equations in Turbulence

The Physics of Fluids, 1970
Turbulence transport equations, describing the dynamics of transient flow of an incompressible fluid in arbitrary geometry, have been derived in such a manner as to incorporate the principles of invariance (tensor and Galilean) and universality. The equations are described in detail and their applicability is demonstrated by comparison of solutions ...
Bart J. Daly, Francis H. Harlow
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