Study on Langevin model parameters of velocity in turbulent shear flows
| Autor: | Anne Tanière, Boris Arcen, Jacek Pozorski, Benoît Oesterlé |
|---|---|
| Přispěvatelé: | Laboratoire Énergies et Mécanique Théorique et Appliquée (LEMTA ), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2010 |
| Předmět: |
Computational Mechanics
02 engineering and technology 01 natural sciences 010305 fluids & plasmas Pipe flow Physics::Fluid Dynamics symbols.namesake Stochastic differential equation 020401 chemical engineering 0103 physical sciences Statistical physics [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph] 0204 chemical engineering ComputingMilieux_MISCELLANEOUS Fluid Flow and Transfer Processes Physics Turbulent diffusion Turbulence Mechanical Engineering Reynolds number Particle-laden flows Mechanics Condensed Matter Physics Open-channel flow Mechanics of Materials symbols Shear flow |
| Zdroj: | Physics of Fluids Physics of Fluids, American Institute of Physics, 2010, 22 (11), pp.115101. ⟨10.1063/1.3489123⟩ |
| ISSN: | 1070-6631 1089-7666 |
| Popis: | This paper deals with the stochastic equation used to predict the fluctuating velocity of a fluid particle in a nonhomogeneous turbulent flow, in the frame of probability density function (PDF) approaches. It is shown that a Langevin-type equation is appropriate provided its parameters (drift and diffusion matrices) are suitably specified. By following the approach proposed in the literature for homogeneous turbulent shear flows, these parameters have been identified using data from direct numerical simulations (DNS) of both channel and pipe flows. Using statistics extracted from the computation of the channel flow, it is shown that the drift matrix of the stochastic differential equation can reasonably be assumed to be diagonal but not spherical. This behavior of the drift coefficients is confirmed by the available results for a turbulent pipe flow at low Reynolds number. Concerning the diffusion matrix, it is found that this matrix is anisotropic for low Reynolds number flows, a property which has been ... |
| Databáze: | OpenAIRE |
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