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

In Search of Airworthy Trailing-Edge Noise Reduction Means

Herr, Michaela and Reichenberger, Johann (2011) In Search of Airworthy Trailing-Edge Noise Reduction Means. In: AIAA Paper 2011-2780. 17th AIAA/CEAS Aeroacoustics Conference, 6.-8. Juni 2011, Portland, Oregon, USA.

[img] PDF - Registered users only
1MB

Abstract

The EC co-financed project OPENAIR aims at a further development of both innovative and established aircraft noise reduction technologies. Among these activities an innovative two-component trailing-edge (TE) design, applicable at a slat TE, was evaluated through generic tests in DLR's Acoustic Wind-Tunnel Braunschweig(AWB). The proposed design combines a supporting frame structure (a coarse metal mesh or rib structure) with a thin, hydraulically smooth cover material (a fine metal mesh, micro-perforated sheet metal or cloth material) which are both permeable to the flow. The result is a mainly hollow, flow-transparent TE region. Variants of this concept were parametrically tested versus a solid reference TE at a 0.4-m chord generic airfoil. Material selection was based on airwor- thiness considerations. Detailed flow/acoustic resistance measurements were performed to characterise the used materials. TE noise was measured by a directional microphone system. The tested TE modifications achieve a broadband noise reduction of up to 4 dB, de-pendent of the configuration. However, the noise reduction effect diminishes with growing angle-of attack. This adverse behavior as well as geometrical dependences will have to be further studied prior to large scale testing. Pressure distribution measurements reveal a non-measurable to small effect of the TE modifications on the airfoil's suction peak. Basic noise scaling laws for transposition of the results to full-scale applications are suggested.

Item URL in elib:https://elib.dlr.de/73635/
Document Type:Conference or Workshop Item (Speech, Paper)
Additional Information:contact: michaela.herr@dlr.de
Title:In Search of Airworthy Trailing-Edge Noise Reduction Means
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Herr, Michaelamichaela.herr (at) dlr.deUNSPECIFIED
Reichenberger, Johannjohann.reichenberger (at) eads.netUNSPECIFIED
Date:June 2011
Journal or Publication Title:AIAA Paper 2011-2780
Refereed publication:No
Open Access:No
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:airframe noise reduction, airworthiness, mesh material, acoustic/flow resistance
Event Title:17th AIAA/CEAS Aeroacoustics Conference
Event Location:Portland, Oregon, USA
Event Type:international Conference
Event Dates:6.-8. Juni 2011
Organizer:American Institute for Aeronautics and Astronautics, AIAA
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Aeronautics
HGF - Program Themes:L VU - Air Traffic and Environment (old)
DLR - Research area:Aeronautics
DLR - Program:L VU - Air Traffic and Environment
DLR - Research theme (Project):L - Quiet Air Traffic (old)
Location: Braunschweig
Institutes and Institutions:Institute of Aerodynamics and Flow Technology > Technical Acoustics
Deposited By: Herr, Michaela
Deposited On:09 Jan 2012 13:53
Last Modified:12 Dec 2013 21:32

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.