Maio 2014 vol. 1 num. 1 - 10th World Congress on Computational Mechanics
Full Article - Open Access.
In order to analyze the effects of mistuning of blisks, the frequency response function (FRF) has to be calculated as quickly as possible and with high accuracy. Therefore, commonly used finite element models with more than 106 degrees of freedom (DOF) have to be reduced to a model with only a few DOF. A usual way in literature is using reduced order models (ROM) like a modal reduction. This is either slow, inaccurate, or the possible extension to non-linearity is difficult. In this paper a new method of model reduction for mistuned turbine blades is introduced and the benefits are shown. The model of the blisk is separated into individually mistuned blades and a tuned disk where the latter is analyzed as a cyclic system. Analog to the Craig-Bampton reduction technique the system is divided into master- and slave-DOF. The introduced technique is the reduction based on the Krylov-Subspace-Method which performs better in terms of accuracy than the modal reduction if the Two-Side-Arnoldi algorithm is used. Afterwards, the reduced tuned model is mistuned by a variation of Youngs modulus which is the most popular way to introduce mistuning. This reduced system can be further described by modal reduction to decouple the equation of motion and describes the full system with as few DOF as possible. Finally, the paper gives a comparison of the standard Craig-Bampton-reduction and the combined Krylov-Craig-Bampton-method in terms of computational accuracy and efficiency to show the benefits of the new method.
Palavras-chave: Mistuning, Krylov-Subspace, Craig-Bampton.,
-  Whitehead D. S., “Effect of Mistuning on the Vibration of Turbomachine Blades Induced by Wakes”. Journal Mechanical Engineering Science 1966.
-  YangM.-T., Griffin J. H., “A Reduced-OrderModel ofMistuning Using a Subset of Nominal System Modes”. Journal of Engineering for Gas Turbines and Power 2001.
-  Feiner D. M. ,Griffin J.H., “A Fundamental Model of Mistuning for a Single Family of Modes”. Journal of Turbomachinery 2002.
-  Hohl A., Siewert C., “A Substructure Based Reduced Order Model for Mistuning Bladed Disks”. ASME Turbo Expo, Vancouver, 2009.
-  Bladh R., Castanier M.P., Pierre C., “Component-Mode-Based Reduced Order Modeling Techniques for Mistuned Bladed Disks - Part I: Theoretical Models”. Journal of Engineering for Gas Turbines and Power 2001.
-  Martel C., “Asymptotic Description of Maximum Mistuning Aamplification of Bladed Disk Forced Response”. ASME Turbo Expo, Berlin 2005.
-  Marinescu O., Equreanu B.I., Banu M., “Reduced Order Models of Mistuned Cracked Bladed Disks”. Journal of Vibration and Acoustics 2011.
-  Antoulas A. C., “Approximation of Large-Scale Dynamical Systems”. Advances in Design and Control, siam 2005.
-  Cook R. D.,Malkus D. S., Plesha M. E., and Witt R. J., “Concepts and Applications of Finite Element Analysis” 4. edition ed. John Wiley and Sons, Chichester. 2002.
-  Salimbahrami B., Lohmann B., “Order Reduction of Large Scale Second-Order Systems Using Krylov Subspace Methods”. Linear Algebra and its Applications 415(2006) 385- 405 2005.
-  Craig R. R., “Coupling of Substructures for Dynamic Analysis: An Overview”. AIAA- 2000-1573 2000.
Pohle, M. Sc. L.; Scheidt, Dr.-Ing. Lars Panning-von; Wallaschek, Prof. Dr.-Ing. Jörg; "REDUCED ORDER MODEL OF MISTUNED BLADED DISKS USING THE KRYLOV-SUBSPACE COMBINEDWITH THE CRAIG-BAMTON REDUCTION TECHNIQUE", p. 899-908 . In: In Proceedings of the 10th World Congress on Computational Mechanics [= Blucher Mechanical Engineering Proceedings, v. 1, n. 1].
São Paulo: Blucher,
ISSN 2358-0828, DOI 10.5151/meceng-wccm2012-18187
últimos 30 dias | último ano | desde a publicação