0

Full Content is available to subscribers

Subscribe/Learn More  >

The Effect of a Bend-Slot Casing Treatment on the Blade Tip Flow Field of a Transonic Compressor Rotor

[+] Author Affiliations
M. Voges, C. Willert, R. Mönig

German Aerospace Center (DLR), Köln, Germany

H.-P. Schiffer

Technische Universität Darmstadt, Darmstadt, Germany

Paper No. GT2013-94006, pp. V06AT35A001; 10 pages
doi:10.1115/GT2013-94006
From:
  • ASME Turbo Expo 2013: Turbine Technical Conference and Exposition
  • Volume 6A: Turbomachinery
  • San Antonio, Texas, USA, June 3–7, 2013
  • Conference Sponsors: International Gas Turbine Institute
  • ISBN: 978-0-7918-5522-5
  • Copyright © 2013 by ASME

abstract

The application of casing treatments (CT) is an effective measure to increase the stable operating range of modern aero engine or gas turbine compressors. As the development and design process of optimized CT geometries is primarily based on numerical simulations, the need for accurate experimental flow field data for related code validation is increasing with the number of applications. While the stall margin enhancement and other stage characteristics can be verified using conventional measurement techniques such as pressure and temperature probes, a deeper insight to the aerodynamic effect of the CT on the rotor flow field can only be provided using non-intrusive, laser-based flow field diagnostics, given that optical access to the compressor stage can be established.

The investigation presented herein involved particle image velocimetry (PIV) measurements at high spatial resolution in the blade tip region of the Darmstadt Transonic Compressor Rotor-1 under the influence of a bend-slot CT. Tangential PIV measurement planes were placed at 95% span as well as in the tip gap of the rotor. The investigation included operating conditions at the aerodynamic design point (peak efficiency) and near stall conditions at 100% rpm. Additional reference measurements were performed with the untreated, smooth casing. The experimental study was complimented by numerical simulations of the same compressor and CT geometry using the DLR TRACE code. Based on the combination of both, experimental and numerical flow field results, a detailed analysis of the shock structures and the tip clearance vortex under the influence of the CT was performed.

Under the influence of the CT, the fluid exchange between rotor passage and CT slots — driven by the pressure gradient over the blade tip and the leading edge bow shock, respectively — induces secondary flow structures in the tip vortex regime. At near stall conditions the periodical injection of energized fluid out of the CT cavities was identified to be one of the major effects stabilizing the tip clearance vortex and hence delaying the onset of rotating stall.

Copyright © 2013 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In