Nonlinear hydroelastic vibration of a cylindrical tank with an elastic bottom containing liquid- analysis using harmonic balance method

摘要

Theoretical analyses and experimental studies have been carried out on the non-linear hydro- elastic vibration of a cylindrical tank with an elastic bottom. In this paper, nonlinear axisym- metric free vibration analysis of the bottom plate of the tank, coupled witb that of the liquid contained within it, is presented by means of the harmonic balance method. In the analysis, the effect of an in-plane force in the plate due to static liquid pressure is taken into account. The effect of the liquid on the non-linearity of the backbone curve of the super-harmonic and the sub-harmonic resonances as well as the principal resonance of both sloshing- and bulging- type responses was clarified, and it was found that with an increase of liquid height. the non- linearity with a hard-spring type of the bottom plate decreased in degree, and became close to linear cbaracteristics. The influence of the bottom plate motions on the free surface response amplitude in the first bulging-type resonunce region was also investigated.