Accession Number : ADA296122

Title :   Structural Dynamics of Mistuned Spatially Periodic Mechanical Systems.

Descriptive Note : Final rept. 1 Sep 91-28 Feb 95,

Corporate Author : SOUTHERN UNIV BATON ROUGE LA

Personal Author(s) : Azene, M. ; Bajaj, A. K. ; Nwokah, O. D.

PDF Url : ADA296122

Report Date : APR 1995

Pagination or Media Count : 5

Abstract : The dynamics of mistuned cyclic systems with special reference to strongly coupled bladed disk assemblies has been investigated. The analysis has utilized ideas from group representation theory, bifurcation theory, singular perturbation theory and modal analysis techniques. The general analysis methodology developed herein is applicable any disk attached with a set of n blades which are strongly coupled cyclically, and mistuning or variations can arise in any of the system parameters. In particular, the study provides qualitative and more importantly, quantitative information in the form of uniformly valid asymptotic expansions for the eigen- frequencies and the modal vectors of the structure. These expansions are used to describe the phenomenon of eigenvalue veering, modal rotations, and other manifestations of the sensitive dependence of eigenfunctions on system parameters lead to modal bifurcations in the forced response of mistuned cyclic systems. Since this approach is general and systematic, the methodology developed is also extended and applied to other discrete and continuous structures as well. (MM)

Descriptors :   *VIBRATION, *EIGENVALUES, *BLADES, *TUNING, *DISKS, STRUCTURAL PROPERTIES, EIGENVECTORS, CYCLES, DEGREES OF FREEDOM, ASYMPTOTIC SERIES, PERTURBATION THEORY, TOLERANCES(MECHANICS), AMPLITUDE, BIFURCATION(MATHEMATICS), MECHANICAL COMPONENTS, PERIODIC VARIATIONS, GROUPS(MATHEMATICS).

Subject Categories : Machinery and Tools
      Mechanics
      Theoretical Mathematics

Distribution Statement : APPROVED FOR PUBLIC RELEASE