On wall pressure fluctuations and their coupling with vortex dynamics in a separated-reattached turbulent flow over a blunt flat plate - Laboratoire Interdisciplinaire des Sciences du Numérique Access content directly
Journal Articles International Journal of Heat and Fluid Flow Year : 2016

On wall pressure fluctuations and their coupling with vortex dynamics in a separated-reattached turbulent flow over a blunt flat plate

Abstract

This study deals with the numerical predictions through Large-Eddy Simulation (LES) of the separated–reattached turbulent flow over a blunt flat plate for analyzing main coherent structure features and their relation to the unsteady pressure field. A compressible approach that inherently includes acoustic propagation is here followed to describe the relationship between pressure fluctuations and vortex dynamics around the separation bubble. The objective of the present work is then to contribute to a better understanding of the coupling between the vortex dynamics and the wall pressure fluctuations. The filtered compress-ible Navier-Stokes equations are then solved with a numerical method that follows a Lax-Wendroff approach to recover a high accuracy in both time and space. For validations, the present numerical results are compared to experimental measurements, coming from both the Pprime laboratory [48] and the literature [9, 32, 52, 48]. Our numerical results very well predict mean and fluctuating pressure and velocity fields. Flapping, shedding as well as Kelvin-Helmholtz characteristic frequencies educed by present simulations are in very good agreement with the experimental values generally admitted. These characteristic modes are also visible on unsteady pressure signatures even far away from the separation. Spectral, POD and EPOD (extended POD) analyses are then applied to these numerical data to enhance the salient features of the pressure and velocity fields, especially the unsteady wall pressure in connection with either the vortex shedding or the low frequency shear-layer flapping. A contribution to the understanding of the coupling between wall pressure fluctuations and eddy vortices is finally proposed.
Fichier principal
Vignette du fichier
HFF7988_finalversion.pdf (3.19 Mo) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

hal-01413083 , version 1 (09-12-2016)

Identifiers

Cite

Christian Tenaud, Bérengère Podvin, Yann Fraigneau, Virginie Daru. On wall pressure fluctuations and their coupling with vortex dynamics in a separated-reattached turbulent flow over a blunt flat plate. International Journal of Heat and Fluid Flow, 2016, 61, Part B, pp.730-748. ⟨10.1016/j.ijheatfluidflow.2016.08.002⟩. ⟨hal-01413083⟩
239 View
352 Download

Altmetric

Share

Gmail Facebook X LinkedIn More