We use POD and EPOD (extended POD) analysis to extract the main features of the flow over a thick flat plate simulated with an LES. Our goal is to better understand the coupling between the velocity field and the surface pressure field. We find that POD modes based on the full velocity and energy fields contain both flapping and shedding frequencies. Pressure modes are found to be uniform in the spanwise direction and the most intense variations take place at the mean reattachment point. Velocity modes educed from the pressure modes with EPOD are seen to correspond to eddies shed by the recirculation bubble.
On considère l'écoulement au-dessus d'une plaque plane épaisse. Nous utilisons la simulation aux grandes échelles et l'analyse POD/EPOD pour comprendre le couplage entre le champ de vitesse et le champ de pression à la paroi. Les modes POD extraits de la vitesse contiennent des fréquences correspondant aux phénomènes de flapping et de shedding. Les modes de pression sont uniformes dans la direction transverse et les variations les plus intenses sont observées au point de réattachement. Les modes de vitesse construits à partir des modes de pression avec l'approche EPOD correspondent à des tourbillons associés à la bulle de recirculation.
Accepted:
Published online:
Mots-clés : Séparation, POD, Couplage vitesse–pression
Bérengère Podvin 1; Yann Fraigneau 1; Christian Tenaud 1; Virginie Daru 1
@article{CRMECA_2014__342_6-7_417_0, author = {B\'ereng\`ere Podvin and Yann Fraigneau and Christian Tenaud and Virginie Daru}, title = {Coherent structures in the boundary layer of a flat thick plate}, journal = {Comptes Rendus. M\'ecanique}, pages = {417--424}, publisher = {Elsevier}, volume = {342}, number = {6-7}, year = {2014}, doi = {10.1016/j.crme.2014.05.006}, language = {en}, }
TY - JOUR AU - Bérengère Podvin AU - Yann Fraigneau AU - Christian Tenaud AU - Virginie Daru TI - Coherent structures in the boundary layer of a flat thick plate JO - Comptes Rendus. Mécanique PY - 2014 SP - 417 EP - 424 VL - 342 IS - 6-7 PB - Elsevier DO - 10.1016/j.crme.2014.05.006 LA - en ID - CRMECA_2014__342_6-7_417_0 ER -
%0 Journal Article %A Bérengère Podvin %A Yann Fraigneau %A Christian Tenaud %A Virginie Daru %T Coherent structures in the boundary layer of a flat thick plate %J Comptes Rendus. Mécanique %D 2014 %P 417-424 %V 342 %N 6-7 %I Elsevier %R 10.1016/j.crme.2014.05.006 %G en %F CRMECA_2014__342_6-7_417_0
Bérengère Podvin; Yann Fraigneau; Christian Tenaud; Virginie Daru. Coherent structures in the boundary layer of a flat thick plate. Comptes Rendus. Mécanique, Flow separation control, Volume 342 (2014) no. 6-7, pp. 417-424. doi : 10.1016/j.crme.2014.05.006. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2014.05.006/
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