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

Combination of a time- and space-resolved measurement technique for laminar-turbulent transition detection

Dimond, Benjamin and Costantini, Marco and Koch, Stefan and Klein, Christian (2020) Combination of a time- and space-resolved measurement technique for laminar-turbulent transition detection. In: 20th Onera-DLR Aerospace Symposium ODAS. 20th Onera-DLR Aerospace Symposium ODAS, 17.-19. November 2020, Braunschweig, Germany (virtuell).

Full text not available from this repository.

Official URL: https://intranet.dlr.de/Seiten/InhaltReduziert.aspx?termId=96a0d225-41bb-4454-82d3-9fa2fef13528&itemid=b25be3c2-b5dd-4e1d-97ea-64de131c29d7&containerid=d755d16b-0e19-4ea3-9c18-3a3809b386cf&vTerms=ContentByTopic

Abstract

Laminar flow technology is a promising way to significantly reduce aerodynamic drag. The underlying mechanisms that lead to laminar-turbulent transition are important knowledge required for accurate design development of low-drag aircraft. Still, detailed information on both boundary-layer stability and transition, is challenging to acquire simultaneously in experiments at flight-relevant flow conditions. This research combines two measurement techniques to develop a method for simultaneous measurement of boundary-layer stability and transition at flight-relevant Mach and Reynolds numbers. Measurements were conducted in the Cryogenic Ludwieg-Tube Göttingen (DNW-KRG) for chord Reynolds numbers ranging from 3.5 to 8 million, Mach numbers from 0.3 to 0.75 and various stream-wise pressure gradients. A 2D wind-tunnel model (chord length 0.2 m), designed to have a large area of uniform pressure gradient on the examined surface, is equipped with both temperature-sensitive paint (TSP) for non-intrusive transition detection and surface hot-films for highly time-resolved measurement of boundary-layer disturbances. For a large part of the tested conditions, both measurement techniques show a noteable overlap in the transition regions. For the first time Tollmien-Schlichting waves could be identified with frequencies above 30 kHz for flow conditions relevant for transport aircraft at high Mach numbers, agreeing with linear stability theory. The described measurement technique enables an experimental proof to predicted mechanisms leading to transition for flight relevant flow conditions.

Item URL in elib:https://elib.dlr.de/138011/
Document Type:Conference or Workshop Item (Speech)
Additional Information:ODAS2020 was held virtually
Title:Combination of a time- and space-resolved measurement technique for laminar-turbulent transition detection
Authors:
AuthorsInstitution or Email of AuthorsAuthor's ORCID iD
Dimond, Benjaminbenjamin.dimond (at) dlr.deUNSPECIFIED
Costantini, Marcomarco.costantini (at) dlr.dehttps://orcid.org/0000-0003-0642-0199
Koch, StefanStefan.Koch (at) dlr.deUNSPECIFIED
Klein, Christianchristian.klein (at) dlr.dehttps://orcid.org/0000-0001-7592-6922
Date:2020
Journal or Publication Title:20th Onera-DLR Aerospace Symposium ODAS
Refereed publication:Yes
Open Access:No
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Status:Published
Keywords:Laminar-turbulent transition, Temperature-sensitive paint, Tollmien-Schlichting waves, Hot-film anemometry, Linear stability analysis
Event Title:20th Onera-DLR Aerospace Symposium ODAS
Event Location:Braunschweig, Germany (virtuell)
Event Type:international Conference
Event Dates:17.-19. November 2020
Organizer:DLR/Onera
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Aeronautics
HGF - Program Themes:fixed-wing aircraft
DLR - Research area:Aeronautics
DLR - Program:L AR - Aircraft Research
DLR - Research theme (Project):L - Simulation and Validation (old)
Location: Göttingen
Institutes and Institutions:Institute for Aerodynamics and Flow Technology > Experimental Methods, GO
Institute for Aerodynamics and Flow Technology > High Speed Configurations, GO
Deposited By: Micknaus, Ilka
Deposited On:09 Dec 2020 21:54
Last Modified:09 Dec 2020 21:54

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.