Vibration modeling of bladed disks subject to geometric mistuning and design changes

Sang Ho Lim, Matthew P. Castanier, Christophe Pierre

Research output: Contribution to journalConference articlepeer-review

50 Scopus citations

Abstract

In this paper, a new reduced-order modeling technique is presented for bladed disks that feature large, geometric deviations from a nominal design. Various finite-element-based reduced-order models (ROMs) have been proposed in the literature for bladed disks with small blade-to-blade differences, called mistuning. Many of these techniques rely on the fact that mistuned-system normal modes can be effectively represented using a linear combination of the normal modes of the nominal (tuned) system. However, when the mistuning or geometric deviation is large, the number of tuned-system normal modes required to describe the mistuned-system normal modes increases dramatically. In this work, a method for large mistuning is formulated by employing a mode-acceleration method with static mode compensation. By accounting for the effects of mistuning as though they were produced by external forces, a set of basis vectors is established using a combination of tuned-system normal modes compensated by static modes. The obtained basis vectors approximately span the space of the mistuned-system modes without requiring a much more expensive modal analysis of the mistuned system, and they provide much better convergence than tuned-system normal modes. Furthermore, in order to extend the method to higher frequency ranges, quasi-static modes, in which inertia effects are included, are employed in place of static modes in the modeacceleration formulation. It is seen that ROMs based on the new technique are extremely compact, yet they accurately capture the vibration response of bladed disks subject to geometric mistuning or design changes.

Original languageEnglish
Pages (from-to)1931-1950
Number of pages20
JournalCollection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
Volume3
DOIs
StatePublished - 2004
EventCollect. of Pap. - 45th AIAA/ASME/ASCE/AHS/ASC Struct., Struct. Dyn. and Mater. Conf.; 12th AIAA/ASME/AHS Adapt. Struct. Conf.; 6th AIAA Non-Deterministic Approaches Forum; 5th AIAA Gossamer Spacecraft Forum - Palm Springs, CA, United States
Duration: 19 Apr 200422 Apr 2004

Fingerprint

Dive into the research topics of 'Vibration modeling of bladed disks subject to geometric mistuning and design changes'. Together they form a unique fingerprint.

Cite this