AEROELASTIC FLUTTER OF CIRCULAR ROTATING DISKS: A SIMPLE PREDICTIVE MODEL

✍ Scribed by H.-R. KIM; A.A. RENSHAW

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 269 KB
• Volume: 256
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.2001.4203

✦ Synopsis

This paper is an attempt to predict aeroelastic #utter of a rotating disk in an unbounded #uid. In the "rst part of the paper, the linear vibration of a rotating, potential #uid driven by transverse, harmonic motion of a rotating disk is solved. We extend the existing solution for a rigid disk to include #exible disks and compare alternative numerical evaluation schemes. Our principal interest in this problem is the identi"cation of possible physical mechanisms for aeroelastic #utter. In the forced vibration problem considered here, #uid rotation renders the governing equations hyperbolic for low-frequency oscillation. As a result, the #uid motion may be discontinuous along the two characteristics that emanate from the rim of the disk. These discontinuities suggest the presence of previously unrecognized boundary layers near the rim of the disk that may be important for aeroelastic #utter. This idea is used to develop a simple mathematical model for predicting aeroelastic #utter. The model and its dependence on the dimensionless parameters describing the system are derived from "rst principles except for the compressible boundary layer, which is described by a simple function whose magnitude is empirically determined by "tting experimental data. Although the model is simple, its predictions are quantitatively similar to the experimental evidence and gives analytic predictions of aeroelastic #utter that are within an order of magnitude of the experimental values.