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

Investigation of trailing-edge noise sources by means of high-speed PIV

Schröder, A. and Herr, M. and Dierksheide, U., LaVision, and Wolf, J., La. Vision, and Kompenhans, J. (2004) Investigation of trailing-edge noise sources by means of high-speed PIV. DLR/ONERA - Annex II Meting, DLR, Köln, 6.-7.04.2004.

Full text not available from this repository.

Abstract

Turbulent boundary layers near the trailing-edge of a surface are known to generate intense, broadband scattering noise as well as surface pressure fluctuations. The noise generating mechanisms depend essentially on the radial components of the velocity fluctuations in respect to the trailing edge. Resulting forces may also cause model vibrations, which are additional low frequency noise sources. The high-speed PIV (HS-PIV) technique is applied to an investigation of the spatial and temporal development of coherent structures in a turbulent flat-plate boundary layer flow in the vicinity of the trailing-edge. With time resolved PIV data obtained in the region immediately up- and downstream of the trailing edge an identification of the flow structure movement, which cause the noise sources is possible. On the basis of a large number of time resolved instantaneous velocity vector fields the technique enables also the possibility of determining several statistical quantities of fluid mechanical significance: average velocity profiles, velocity fluctuations (u´, v´), rms-fields, probability density functions and space-time-correlations of the velocity fluctuations, the instantaneous Reynolds stresses (u´v´) of all four quadrants and the z-component of vorticity. A flat plate with an elliptic leading edge was mounted vertically in the AWB, the low noise wind tunnel of DLR, Braunschweig. At a free stream velocity of U = 40 and 50m/s and a stream-wise length of the flat plate of x = 2 m a turbulent boundary layer flow develops and the flow structures convect past the trailing edge.

Document Type:Conference or Workshop Item (Speech)
Additional Information: LIDO-Berichtsjahr=2004,
Title:Investigation of trailing-edge noise sources by means of high-speed PIV
Authors:
AuthorsInstitution or Email of Authors
Schröder, A.UNSPECIFIED
Herr, M.UNSPECIFIED
Dierksheide, U., LaVision, UNSPECIFIED
Wolf, J., La. Vision, UNSPECIFIED
Kompenhans, J.UNSPECIFIED
Date:2004
Page Range:1-
Status:Published
Keywords:High speed PIV, trailing-edge noise, turbulent boundary layer, coherent structures
Event Title:DLR/ONERA - Annex II Meting, DLR, Köln, 6.-7.04.2004
Organizer:DLR/ONERA
HGF - Research field:Aeronautics, Space and Transport (old)
HGF - Program:Aeronautics
HGF - Program Themes:Aircraft Research
DLR - Research area:Aeronautics
DLR - Program:L AR - Aircraft Research
DLR - Research theme (Project):L - Flight Physics
Location: Köln-Porz , Braunschweig , Göttingen
Institutes and Institutions:Institute of Aerodynamics and Flow Technology
Deposited By: Ilka Micknaus
Deposited On:31 Jan 2006
Last Modified:14 Jan 2010 19:30

Repository Staff Only: item control page

Browse
Search
Help & Contact
Informationen
electronic library is running on EPrints 3.3.12
Copyright © 2008-2012 German Aerospace Center (DLR). All rights reserved.