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Title: Artificial Fluid Properties for Large-Eddy Simulation of Compressible Turbulent Mixing

Abstract

An alternative methodology is described for Large-Eddy Simulation of flows involving shocks, turbulence and mixing. In lieu of filtering the governing equations, it is postulated that the large-scale behavior of an ''LES'' fluid, i.e., a fluid with artificial properties, will be similar to that of a real fluid, provided the artificial properties obey certain constraints. The artificial properties consist of modifications to the shear viscosity, bulk viscosity, thermal conductivity and species diffusivity of a fluid. The modified transport coefficients are designed to damp out high wavenumber modes, close to the resolution limit, without corrupting lower modes. Requisite behavior of the artificial properties is discussed and results are shown for a variety of test problems, each designed to exercise different aspects of the models. When combined with a 10th-order compact scheme, the overall method exhibits excellent resolution characteristics for turbulent mixing, while capturing shocks and material interfaces in crisp fashion.

Authors:
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
902334
Report Number(s):
UCRL-CONF-227155
TRN: US200717%%260
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: Presented at: International Workshop on the Physics of Compressible Turbulent Mixing, Paris, France, Jul 17 - Jul 21, 2006
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUMM MECHANICS, GENERAL PHYSICS; MODIFICATIONS; PHYSICS; RESOLUTION; SHEAR; SIMULATION; THERMAL CONDUCTIVITY; TRANSPORT; TURBULENCE; VISCOSITY

Citation Formats

Cook, A W. Artificial Fluid Properties for Large-Eddy Simulation of Compressible Turbulent Mixing. United States: N. p., 2007. Web.
Cook, A W. Artificial Fluid Properties for Large-Eddy Simulation of Compressible Turbulent Mixing. United States.
Cook, A W. Mon . "Artificial Fluid Properties for Large-Eddy Simulation of Compressible Turbulent Mixing". United States. doi:. https://www.osti.gov/servlets/purl/902334.
@article{osti_902334,
title = {Artificial Fluid Properties for Large-Eddy Simulation of Compressible Turbulent Mixing},
author = {Cook, A W},
abstractNote = {An alternative methodology is described for Large-Eddy Simulation of flows involving shocks, turbulence and mixing. In lieu of filtering the governing equations, it is postulated that the large-scale behavior of an ''LES'' fluid, i.e., a fluid with artificial properties, will be similar to that of a real fluid, provided the artificial properties obey certain constraints. The artificial properties consist of modifications to the shear viscosity, bulk viscosity, thermal conductivity and species diffusivity of a fluid. The modified transport coefficients are designed to damp out high wavenumber modes, close to the resolution limit, without corrupting lower modes. Requisite behavior of the artificial properties is discussed and results are shown for a variety of test problems, each designed to exercise different aspects of the models. When combined with a 10th-order compact scheme, the overall method exhibits excellent resolution characteristics for turbulent mixing, while capturing shocks and material interfaces in crisp fashion.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 08 00:00:00 EST 2007},
month = {Mon Jan 08 00:00:00 EST 2007}
}

Conference:
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