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A vortex-based model for the subgrid flux of a passive scalar

Pullin, D. I. (2000) A vortex-based model for the subgrid flux of a passive scalar. Physics of Fluids, 12 (9). pp. 2311-2319. ISSN 1070-6631. doi:10.1063/1.1287512. https://resolver.caltech.edu/CaltechAUTHORS:PULpof00

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Abstract

A model for the flux of a passive scalar by the subgrid motions in the large-eddy simulation of turbulent flow is proposed within the framework of the stretched-vortex subgrid stress model. The model is based on an analytical solution for the winding of a scalar field by an elemental subgrid vortex. This gives a tensor gradient-diffusion expression for the local flux of the scalar with subgrid turbulent diffusivity which depends upon the subgrid energy, the local cell size, and the vortex orientation in space. The scalar-flux subgrid model is tested by comparison of the results of 323 large-eddy simulation of passive-scalar transport by forced isotropic turbulence in the presence of a mean scalar gradient, with the direct-numerical simulation results of Overholt and Pope [Phys. Fluids 8, 2128 (1996)]. The present large-eddy simulation results predict that at large Taylor–Reynolds numbers, the ratio of the scalar variance to the squared product of the scalar gradient with the dissipation length of the turbulence, is asymptotic to a nearly constant value c[prime]2/(alpha1 Lepsilon)2[approximate]0.36.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.1063/1.1287512DOIUNSPECIFIED
Additional Information:©2000 American Institute of Physics. (Received 29 September 1999; accepted 1 June 2000) This work was supported in part by the National Science Foundation under Grant No. CTS-9978551.
Group:GALCIT
Subject Keywords:turbulence; vortices; flow simulation
Issue or Number:9
DOI:10.1063/1.1287512
Record Number:CaltechAUTHORS:PULpof00
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:PULpof00
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:2399
Collection:CaltechAUTHORS
Deposited By: Archive Administrator
Deposited On:03 Apr 2006
Last Modified:08 Nov 2021 19:47

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