elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Computation of 3D-wave packet characteristics in an unstable boundarysubsonic layer

Delfs, J. (1997) Computation of 3D-wave packet characteristics in an unstable boundarysubsonic layer. EUROMECH 3rd European Fluid Mechanics Conference 1997, 15.-18. Sept. 1997 in Goettingen.

Full text not available from this repository.

Abstract

Realistic perturbations of technical flows are usually of limited spatio-temporal extent (e.g. gusts in the freestream, roughness elements, active control devices etc.). Early results for three-dimensional wave packets in incompressible flow were obtained in (1). Here, the time asymptotic response of the subsonic adiabatic flat plate boundary layer flow upon a pulsewise and localized perturbation is studied theoretically at supercritical Reynolds number using the saddlepoint technique as in (2). The analysis is based on linear theory and is local, i.e. parallel flow is assumed. An unstable disturbance wave packet moves as a whole and spreads out at the same time. Thus, the moving packet defines a set of velocities (U, V) in the (x,y)-plane (x-streamwise, y-spanwiseI by which it's disturbance content is transported. Only an observer, assuming a velocity in this range will see a non- decaying energy density A. It's temporal evolution A (t) measured.

Item URL in elib:https://elib.dlr.de/36551/
Document Type:Conference or Workshop Item (Paper)
Additional Information: LIDO-Berichtsjahr=1997,
Title:Computation of 3D-wave packet characteristics in an unstable boundarysubsonic layer
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Delfs, J.UNSPECIFIEDUNSPECIFIED
Date:1997
Open Access:No
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:wave packet, boundary layer stability, compressible flow, group velocity, wave packet amplification
Event Title:EUROMECH 3rd European Fluid Mechanics Conference 1997, 15.-18. Sept. 1997 in Goettingen
HGF - Research field:UNSPECIFIED
HGF - Program:Aeronautics
HGF - Program Themes:other
DLR - Research area:UNSPECIFIED
DLR - Program:L ST - Starrflüglertechnologien
DLR - Research theme (Project):L - Concepts & Integration (old)
Location: Köln-Porz , Braunschweig , Göttingen
Institutes and Institutions:Institute of Aerodynamics and Flow Technology > Institut für Entwurfsaerodynamik
Deposited By: DLR-Beauftragter, elib
Deposited On:03 Apr 2006
Last Modified:27 Apr 2009 10:06

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.