管束的流体弹性不稳定性的研究

Study of Fluidelastic Instability in Tube Bundles

基于Lever与Weaver的“流管”模型,本文对换热器管束的流体弹性不稳定性进行了较深入的研究。认为管子作周期性的衰减(或发散)运动。基本方程以复数形式表示,并用复数解法来求解。证明了作用在管上的流体力与管子运动时的位移、速度、加速度密切相关。作出的稳定区图可用来判断管子是否发生流体弹性不稳定现象。将节径比为1.25,1.32与1.41的正方形排列的管束,依次放入风洞中进行试验,取得了令人满意的结果。

Basing on Lever's and Weaver's “tube-in-channel”model,the fluidelastic instability of heat exchangertube bundle is thoroughly discussed in this paper.The vibration of the tube is considered as periodic damp-ing(or divergent)motion.The fundamental equations are expressed by complex numbers and solved bycomplex method.It is proved that the fluid force acting on the tube is closely related to the displacement,velocity and acceleration of the tube.By drawing the stability diagram,one may judge whether the tube cre-ats the threshold of fluidelastic instability or not.The experiments are conducted in a wind tunnel.The tube arrays are square with pitch ratios of 1.25,1.32 and 1.41.The experimental data are in good agreement with the theoretical results.