乱流場における流体・構造体連成振動解析手法の開発 : 第2報,円柱の渦励起振動解析と振動機構の検討

概要

論文の詳細を見る
A vortex-induced vibration of an elstically supported cylinder is simulated in two-dimension by using a flow-induced vibration analysis program which has been developed in order to evaluate flow induced vibration in various components such as the heat exchanger. From the comparison of calculated results and the experimental data, the following conclusions could be obtained. (1) Although the vibration amplitudes were overestimated, the synchronization phenomenon between cylinder vibration and Karman vortex shedding could be simulated successfully. (2) The 'lock in' phenomenon, in which a vortex shedding frequency coincides with a cylinder natural frequency in a certain reduced velocity range, could be simulated successfully. (3) The 'lock in' phenomenon occurs when an ordinary vortex shedding pattern is broken by cylinder motion, and synchronization between vortex shedding and cylinder vibration occurs. After synchronization occurs, the vortex shedding pattern becomes the same as in forced vibration.
1994-09-25