DYNAMICS OF AN ARTICULATED CYLINDER IN ANNULAR FLOW VIA NON-LINEAR AND PARTIALLY LINEARIZED VERSIONS OF AN ANALYTICAL MODEL
✍ Scribed by R.M Botez; M.P Paı̈doussis
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 742 KB
- Volume
- 192
- Category
- Article
- ISSN
- 0022-460X
No coin nor oath required. For personal study only.
✦ Synopsis
This paper deals with the non-linear dynamics of an articulated system of two rigid cylinders interconnected by rotational springs, within a pipe conveying fluid, with fluid flowing downward in the relatively narrow annular space. The impacting of the articulated cylinder system on the external pipe is modelled by a cubic spring. The behaviour of the articulated cylinder system is studied for flow velocities higher than the critical value at which a flutter or a divergence instability occurs. Two models are constructed for this system, depending on the form of equations of motion considered: in the first model, the dynamics of the system when no impact occurs with the outer pipe is described by a set of non-linear equations in which the non-linearities are taken into account approximately to order three via Taylor expansions of the trigonometric functions of state variables; in the second case, these equations are linearized. For both models, the dynamical behaviour of the system is illustrated by phase plane portraits, bifurcation diagrams, power spectra and Poincare´sections. The results obtained via these two models are compared qualitatively and quantitatively.