弹性管道三维小雷诺数流中的波动计算

COMPUTATION FOR WAVE OF 3-D LOW REYNOLDS FLOW IN AN ELASTIC PIPE

本文利用文献[1]的杂交之法处理弹性管道三维粘性流体的波动问题,把流动区域分成远场与近场,远场的级数解形式由文献[2]给出,近场仍用有限元方法,但如今必须考虑三维情况。用数值方法求出与远场特征函数相应的特征方程的根,计算结果表明,除基本特征解为二维以外,其余一律衰减甚快。因此,多数情况下可以不计。

A hybrid method [1] is used to solve the wave of 3-D low Reynolds flow in an elastc pipe. The flow region is divided into far field and near fielf. In far field the solutions can be expressed by series expansions[2], while in the near field FEM could be used. 3-D eigen-functions must be taken into account. The corresponding eigen values are calculated numerically. It is shown that except the fundamental eigen functions which are just the 2-D ones, the others decrease very qnickly. So 2-D eigen functious are enough for many cases.