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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Large Eddy Simulations of convergent-divergent channel flows at moderate Reynolds numbers

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Schiavo, Luiz A. C. A. [1] ; Jesus, Antonio B. [2] ; Azevedo, Joao L. F. [3] ; Wolf, William R. [1]
Total Authors: 4
[1] Univ Estadual Campinas, BR-13083970 Campinas, SP - Brazil
[2] Inst Tecnol Aeronaut, BR-12228900 Sao Jose Dos Campos, SP - Brazil
[3] Inst Aeronaut & Espago, BR-12228903 Sao Jose Dos Campos, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Web of Science Citations: 3

The paper is focused on the study of fully turbulent channel flows, using Large Eddy Simulations (LES), in order to address the effects of adverse pressure gradient regions. Analyses of the effects of streak instabilities, which have been shown to be relevant in such regions, are extended to moderate Reynolds numbers. The work considers two different channel geometries in order to further separate influences from wall curvature, flow separation and adverse pressure gradients. Turbulent kinetic energy and Reynolds stress budgets are investigated at separation and re-attachment points. The numerical approach used in the present work is based on the incompressible Navier-Stokes equations, which are solved by a pseudo-spectral methodology for structured grids. Wall-resolved LES calculations are performed using the WALE subgrid scale model. The study shows that the streak instability mechanism persists at higher Reynolds numbers with and without wall curvature in the adverse pressure gradient regions. Moreover, the observed effects are also present regardless of the existence of flow separation regions. Finally, the study of turbulent kinetic energy budgets indicates that, independently of the flow condition, there are well-defined patterns for such turbulent properties at separation and re-attachment points. (C) 2015 Elsevier Inc. All rights reserved. (AU)

FAPESP's process: 13/07375-0 - CeMEAI - Center for Mathematical Sciences Applied to Industry
Grantee:José Alberto Cuminato
Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC
FAPESP's process: 13/03413-4 - Investigation of noise generation and propagation by aerodynamic configurations using computational aeroacoustics
Grantee:William Roberto Wolf
Support type: Research Grants - Young Investigators Grants
FAPESP's process: 14/07623-6 - Numerical study of the effect of a geometric disturbance in turbulent flows
Grantee:Luiz Augusto Camargo Aranha Schiavo
Support type: Scholarships in Brazil - Doctorate