Observatorio de I+D+i UPM

Memorias de investigación
Communications at congresses:
The scenario of two-dimensional instabilities of the cylinder wake under EHD forcing: A linear stability analysis
Year:2011
Research Areas
  • Mechanical aeronautics and naval engineering
Information
Abstract
We propose to study the stability properties of a wake air flow forced by electrohydrodynamic (EHD) actuators, dielectric barrier discharge (DBD) type. EHD actuators can add momentum to the ow around an object in regions close to the wall. As the forcing frequencies, characteristic of DBD, are much higher than the natural shedding frequency of the flow (kHz vs. Hz), we consider in this work the forcing actuation as stationary. The actuators are disposed symmetrically near the boundary layer separation point. We study the ow around a cylinder modi?ed by EHD actuators experimentally by means of particle image velocimetry (PIV) measures and also computationally by solving the generalized eigenvalue problem obtained from linearized Navier-Stokes equations. In the numerical part, the presence of the EHD actuators has been implemented as a boundary condition on the cylinder surface. The base flow obtained computationally using this boundary condition has been compared with the experimental one in order to match the control parameters from both methodologies. Once the base flow agreement has been veri?ed, the Hopf bifurcation produced when the flow starts the vortex shedding has been studied by di?erent methods: ?rst, when the base flow is obtained from experimental snapshots, the evolution of the amplitude velocity oscillations is monitored; second, when the base flow is computationally obtained, a global linearized eigenvalue problem is solved for the instability study. Finally, the critical parameters have been compared.
International
Si
Congress
6th Theoretical Fluid Mechanics Conference.
960
Place
Honolulu, HI, EEUU
Reviewers
Si
ISBN/ISSN
978-1-61839-172-8
Start Date
27/06/2011
End Date
30/06/2011
From page
1
To page
18
The scenario of two-dimensional instabilities of the cylinder wake under EHD forcing: A linear stability analysis
Participants
  • Autor: Leo Miguel Gonzalez Gutierrez (UPM)
Research Group, Departaments and Institutes related
  • Creador: Grupo de Investigación: CEHINAV (Canal de Ensayos Hidrodinámicos de la E.T.S.I. Navales)
  • Departamento: Ciencias Aplicadas a la Ingeniería Naval
S2i 2020 Observatorio de investigación @ UPM con la colaboración del Consejo Social UPM
Cofinanciación del MINECO en el marco del Programa INNCIDE 2011 (OTR-2011-0236)
Cofinanciación del MINECO en el marco del Programa INNPACTO (IPT-020000-2010-22)