Numerical and experimental damping prediction of a nonlinearly coupled low pressure steam turbine blading

verfasst von: Christian Siewert, Lars Panning, Christoph Gerber, Pierre Alain Masserey
Abstract: In this paper, a method for the dynamic analysis of a turbine blading coupled by shrouds and snubbers has been presented. In order to reduce the size of the problem, the modal description has been used in combination with the HBM resulting in a EQM formulated in the modal domain. The revealed system of nonlinear equations is solved in order to obtain the nonlinear frequency response of the blading coupled by shrouds and snubbers. To quantify the amount of damping in the system, the energy dissipation ratio R and the loss factor T||0SS have been defined. To compute these quantities, the energy applied to the blading per cycle, the dissipated energy per cycle and the maximum of the potential energy during a vibration cycle have to be computed. The influence of parameters like the coefficient of friction, the surface roughness or the stimulus on the loss factor have been evaluated numerically for the a real steam turbine blading (ND45A LP LSMB). For the analyzed steam turbine blading, the loss factor determined experimentally and the loss factor determined numerically have been compared. The calculated loss factors are in general in a good agreement to the experimentally determined loss factors. Especially the dependency of the loss factor on the nodal diameter is nearly identical in the numerical and experimental results.
Organisationseinheit(en): Institut für Dynamik und Schwingungen
Externe Organisation(en): Alstom
Typ: Aufsatz in Konferenzband
Seiten: 531-542
Anzahl der Seiten: 12
Publikationsdatum: 06.2008
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Ingenieurwesen (insg.)
Elektronische Version(en): https://doi.org/10.1115/GT2008-51073 (Zugang: Geschlossen)

BibTeX

@inproceedings{3eb2d37c77e24690a2f6d08e2b1a70e2,
title = "Numerical and experimental damping prediction of a nonlinearly coupled low pressure steam turbine blading",
abstract = "In this paper, a method for the dynamic analysis of a turbine blading coupled by shrouds and snubbers has been presented. In order to reduce the size of the problem, the modal description has been used in combination with the HBM resulting in a EQM formulated in the modal domain. The revealed system of nonlinear equations is solved in order to obtain the nonlinear frequency response of the blading coupled by shrouds and snubbers. To quantify the amount of damping in the system, the energy dissipation ratio R and the loss factor T||0SS have been defined. To compute these quantities, the energy applied to the blading per cycle, the dissipated energy per cycle and the maximum of the potential energy during a vibration cycle have to be computed. The influence of parameters like the coefficient of friction, the surface roughness or the stimulus on the loss factor have been evaluated numerically for the a real steam turbine blading (ND45A LP LSMB). For the analyzed steam turbine blading, the loss factor determined experimentally and the loss factor determined numerically have been compared. The calculated loss factors are in general in a good agreement to the experimentally determined loss factors. Especially the dependency of the loss factor on the nodal diameter is nearly identical in the numerical and experimental results.",
author = "Christian Siewert and Lars Panning and Christoph Gerber and Masserey, {Pierre Alain}",
year = "2008",
month = jun,
doi = "10.1115/GT2008-51073",
language = "English",
isbn = "9780791843154",
series = "Proceedings of the ASME Turbo Expo",
number = "PART A",
pages = "531--542",
booktitle = "2008 Proceedings of the ASME Turbo Expo",
edition = "PART A",
note = "2008 ASME Turbo Expo ; Conference date: 09-06-2008 Through 13-06-2008",
}