Largeeddy simulation of heavy particle dispersion in wallbounded turbulent flows
Abstract
Capabilities and accuracy issues in Lagrangian tracking of heavy particles in velocity fields obtained from largeeddy simulations (LES) of wallbounded turbulent flows are reviewed. In particular, it is shown that, if no subgrid scale (SGS) model is added to the particle motion equations, particle preferential concentration and nearwall accumulation are significantly underestimated. Results obtained with SGS modeling for the particle motion equations based on approximate deconvolution are briefly recalled. Then, the error purely due to filtering in particle tracking in LES flow fields is singled out and analyzed. The statistical properties of filtering errors are characterized in turbulent channel flow both from an Eulerian and a Lagrangian viewpoint. Implications for stochastic SGS modeling in particle motion equations are briefly outlined.
 Authors:
 DICI, University of Pisa, I56122 Pisa (Italy)
 Publication Date:
 OSTI Identifier:
 22391039
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 1648; Journal Issue: 1; Conference: ICNAAM2014: International Conference on Numerical Analysis and Applied Mathematics 2014, Rhodes (Greece), 2228 Sep 2014; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCURACY; APPROXIMATIONS; CONCENTRATION RATIO; EQUATIONS OF MOTION; ERRORS; FILTERS; LAGRANGIAN FUNCTION; LARGEEDDY SIMULATION; PARTICLES; STOCHASTIC PROCESSES; TURBULENT FLOW; VELOCITY
Citation Formats
Salvetti, M.V. Largeeddy simulation of heavy particle dispersion in wallbounded turbulent flows. United States: N. p., 2015.
Web. doi:10.1063/1.4912322.
Salvetti, M.V. Largeeddy simulation of heavy particle dispersion in wallbounded turbulent flows. United States. doi:10.1063/1.4912322.
Salvetti, M.V. 2015.
"Largeeddy simulation of heavy particle dispersion in wallbounded turbulent flows". United States.
doi:10.1063/1.4912322.
@article{osti_22391039,
title = {Largeeddy simulation of heavy particle dispersion in wallbounded turbulent flows},
author = {Salvetti, M.V.},
abstractNote = {Capabilities and accuracy issues in Lagrangian tracking of heavy particles in velocity fields obtained from largeeddy simulations (LES) of wallbounded turbulent flows are reviewed. In particular, it is shown that, if no subgrid scale (SGS) model is added to the particle motion equations, particle preferential concentration and nearwall accumulation are significantly underestimated. Results obtained with SGS modeling for the particle motion equations based on approximate deconvolution are briefly recalled. Then, the error purely due to filtering in particle tracking in LES flow fields is singled out and analyzed. The statistical properties of filtering errors are characterized in turbulent channel flow both from an Eulerian and a Lagrangian viewpoint. Implications for stochastic SGS modeling in particle motion equations are briefly outlined.},
doi = {10.1063/1.4912322},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1648,
place = {United States},
year = 2015,
month = 3
}

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No abstract prepared. 