2007 Volume 7 Issue 4 Pages 374-380
An experimental study was conducted to investigate the flow-induced vibration characteristics of socket-supported (flexible) tube bundles in cross flow. In order to simulate the partial support of clearance holes of baffles in shell-and-tube heat exchangers, in-line and staggered bundles comprising glass rods mounted flexibly inside circular supporting socket in the channel wall were constructed. The two test sections were made transparent to facilitate flow visualization and whole-field measurement by PIV. Based on the results obtained in this study, it can be concluded that vortex shedding is the intrinsic excitation source for the vibration of flexible tube bundle. Vortex shedding creates instability in the flow field. The vortex shedding drives the oscillating motion of the tube, and the motion of the tube controls the vortex shedding. Thus a feedback path is established to sustain the tube vibration.
