Full Content is available to subscribers

Subscribe/Learn More  >

Nonlinear Dynamic Analyses of a Gas Turbine Blade for Attainment of Reliable Shroud Coupling

[+] Author Affiliations
J. Szwedowicz

ABB Turbo Systems, Ltd., Baden, Switzerland

S. Slowik, A. Mahler, C. J. Hulme

ALSTOM (Switzerland), Ltd., Baden, Switzerland

Paper No. GT2005-69062, pp. 553-561; 9 pages
  • ASME Turbo Expo 2005: Power for Land, Sea, and Air
  • Volume 4: Turbo Expo 2005
  • Reno, Nevada, USA, June 6–9, 2005
  • Conference Sponsors: International Gas Turbine Institute
  • ISBN: 0-7918-4727-6 | eISBN: 0-7918-3754-8
  • Copyright © 2005 by ASME


The major objective of this paper is to evaluate a stand-point for integral shroud coupling, regarding the complex problem of nonlinear resonance vibrations of a shrouded blade with friction and impact effects. Following the load sequence in the start-up and further uploading to base load, a nonlinear cyclic FE static computation with friction forces at the shroud interface delivers contact stress results essential for assessment of a reliable shroud coupling. The FE refinement study at the shroud interface proves the reliability of the computed eigenfrequencies with respect to the harmonic engine excitation. Using nonlinear dynamic simulations of the shroud connection with friction forces, contact stiffness, surface roughness and impacts, the decoupling between the static and dynamic motions at the shroud interface is demonstrated. Based on the one-dimensional description of vibration characteristics for the shrouded blade, the resulting normal and tangential contact stiffness are evaluated from the computed 3D FE nodal diameter diagrams. The excitation forces acting on the blade are determined with the stimulus concept, in which an empirical factor is estimated from pulsation measured in the combustor chamber over the frequency range of the blade vibrations. The entire process is illustrated for the redesigned Z-lock interface on the shroud of a gas turbine stage whose contact surfaces had shown fretting problems. The numerical results confirm possible contact failures for the old shroud configuration. The blade calculated with the modified shroud connection shows numerically, stable dynamic behavior and will therefore prevent further fretting contact problems.

Copyright © 2005 by ASME



Interactive Graphics


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

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