旋转流不稳定性的一个数值研究

本文研究了在两个同心圆管间具有轴向流动的无粘不可压旋转流的稳定性问题。分析了Ludwieg在窄缝条件下导出的稳定性判据;采用有限差分数值方法计算了在各种条件下的时间增长率;验证了Ludwieg的稳定性判据,并指出:当将结果推广到宽缝和不同的速度剖面时,判据将会产生某些误差。

A Numerical Investigation on the Instability of Swirling Flow

In this paper, the instability of the inviscid incompressible swirlingflow between two concentric cylinders is investigated, Ludwieg's stabilitycriterion derived under the condition of narrow gap is analysed, and thetemporal growth rate in the different conditions is calculated by a finitedifference numerical method. A check on Ludwieg's stability criterionindicates that some errors will occur when this criterion is extended to thecases of the wide gap and different velocity profiles.