dorsal/arxiv
View SchemaPassive scalar diffusion as a damped wave
| Authors | Axel Brandenburg, Petri Käpylä, Amjed Mohammed |
|---|---|
| Categories | |
| ArXiv ID | physics/0404118 |
| URL | https://arxiv.org/abs/physics/0404118 |
| Journal | In: Progress in Turbulence, Eds: J. Peinke et al., Springer-Verlag, pp. 3-6 (2005) |
Abstract
Three-dimensional turbulence simulations are used to show that the turbulent root mean square velocity is an upper bound of the speed of turbulent diffusion. There is a close analogy to magnetic diffusion where the maximum diffusion speed is the speed of light. Mathematically, this is caused by the inclusion of the Faraday displacement current which ensures that causality is obeyed. In turbulent diffusion, a term similar to the displacement current emerges quite naturally when the minimal tau approximation is used. Simulations confirm the presence of such a term and give a quantitative measure of its relative importance.
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"abstract": "Three-dimensional turbulence simulations are used to show that the turbulent\nroot mean square velocity is an upper bound of the speed of turbulent\ndiffusion. There is a close analogy to magnetic diffusion where the maximum\ndiffusion speed is the speed of light. Mathematically, this is caused by the\ninclusion of the Faraday displacement current which ensures that causality is\nobeyed. In turbulent diffusion, a term similar to the displacement current\nemerges quite naturally when the minimal tau approximation is used. Simulations\nconfirm the presence of such a term and give a quantitative measure of its\nrelative importance.",
"arxiv_id": "physics/0404118",
"authors": [
"Axel Brandenburg",
"Petri K\u00e4pyl\u00e4",
"Amjed Mohammed"
],
"categories": [
"physics.flu-dyn"
],
"journal_ref": "In: Progress in Turbulence, Eds: J. Peinke et al.,\n Springer-Verlag, pp. 3-6 (2005)",
"title": "Passive scalar diffusion as a damped wave",
"url": "https://arxiv.org/abs/physics/0404118"
},
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