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

Unsteady boundary layer transition on a high pressure turbine rotor balde

Tiedemann, M. and Kost, F. (1999) Unsteady boundary layer transition on a high pressure turbine rotor balde. ASME TURBO EXPO, 1999.

Full text not available from this repository.

Abstract

This investigation is aimed at the experimental determination of the location, the extent, and the modes of the laminar-to-turbulent transition processes in the boundary layers of a high pressure turbine rotor blade. The results are based on time-resolved, qualitative wall shear stress data which was derived from surface hotfilm measurements. The tests were conducted in the "Windtunnel for Rotating Cascades" of the DLR in Göttingen. For the evaluation of the influence of passing wakes and shocks on the unsteady boundary layer transition, a test with undisturbed rotor inlet flow was conducted in addition to full stage tests. Two different transition modes led to a periodic-unsteady, multimoded transition on the suction side. In between two wakes, transition started in the bypass mode and terminated as separated-flow transition. Underneath the wakes, plain bypass transition occurred. The weak periodic boundary layer features on the pressure side indicate that this surface was not significantly affected by passing wakes or shocks. The acquired data reveals that the periodically disturbed suction side boundary layer is less susceptible to bubble bursting than the undisturbed flowfield. Thus, these blades may be subjected to higher aerodynamic loads. Accordingly, as in low pressure turbines, the unsteady effects in high pressure turbines may allow for a reduction of the number of rotor blades, with respect to the original design

Document Type:Conference or Workshop Item (Speech)
Additional Information: LIDO-Berichtsjahr=1999,
Title:Unsteady boundary layer transition on a high pressure turbine rotor balde
Authors:
AuthorsInstitution or Email of Authors
Tiedemann, M.UNSPECIFIED
Kost, F.UNSPECIFIED
Date:1999
Status:Published
Keywords:high pressure turbine, boundary layer transition, unsteady, hotfilm, transonic
Event Title:ASME TURBO EXPO, 1999
Organizer:ASME
HGF - Research field:Aeronautics, Space and Transport (old)
HGF - Program:Aeronautics
HGF - Program Themes:other
DLR - Research area:Aeronautics
DLR - Program:L TT - Triebwerkstechnologien
DLR - Research theme (Project):UNSPECIFIED
Location: Köln-Porz , Braunschweig , Göttingen
Institutes and Institutions:Institute of Aerodynamics and Flow Technology > Institut für Strömungsmechanik
Deposited By: elib DLR-Beauftragter
Deposited On:16 Sep 2005
Last Modified:14 Jan 2010 20:31

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.