An experimental study of the nonlinear dynamics of cylindrical shells with clamped ends subjected to axial flow

Abstract

This paper presents experimental results on the nonlinear dynamics and stability characteristics of thin-walled clamped-clamped circular cylindrical shells in contact with flowing fluid. The experiments were conducted with three experimental set-ups: one for experiments with elastomer shells in annular air-flow, the second for elastomer shells with internal air-flow, and the last one for aluminium or plastic cylindrical shells with internal water-flow. In all cases the interaction between the shell and the fully developed flow gives rise to instabilities in the form of static or dynamic divergence at sufficiently high flow velocities. The aim of the experimental study was (i) to gather data on the critical flow velocity for instability and on the post-critical flow/displacement-amplitude relationship, and (ii) to undertake an analysis of the experimental results and to compare them qualitatively with theoretical predictions. The experimental results show a softening type nonlinear behaviour, with a large hysteresis in the velocity for the onset and cessation of divergence. r

Vibration of Slender Structures Subjected to Axial Flow or Axially Towed in Quiescent Fluid

“…Clearly, this re-examination must involve both nonlinear theory and further experiments. This was discussed in greater detail by Karagiozis et al [89][90][91] and Païdoussis [13].…”

“…However, they did not develop coupled-model flutter. As the experiments [89] were always done with shells with clamped ends (for experimental convenience), a new nonlinear theoretical model was developed for shells with clamped ends [90,91]. Again, the postdivergence flutter was not detected.…”

Non-linear vibrations of shells: A literature review from 2003 to 2013

“…Experiments on non linear dynamics of clamped shells subjected to axial flow were described in Ref. [121] and its visual experimental evidence was provided in Ref. [122].…”

“…Pellicano [96] extended his previous experimental tests by follow ing a stepped sine approach and obtained the experimental stabi lity diagrams of a shell connected to top mass. Experiments on the stability of shells subjected to fluid flow were carried out by Karagiozis et al [121,122,124,125]. Shells having clamped ends and subjected to external airflow and internal water flow were tested.…”

A fluid–structure interaction model for stability analysis of shells conveying fluid

“…Paı¨doussis (2005) reviewed some unresolved issues and paradoxes in fluid-structure interaction problems in fluid-conveying pipes and shells. Karagiozis et al (2005) presented experimental results on the nonlinear dynamics and stability characteristics of thinwalled clamped-clamped circular cylindrical shells. The experiments were carried out for elastomer shells in annular airflow, elastomer shells with internal air-flow, and aluminum and plastic cylindrical shells with internal water-flow.…”