A Two-Dimensional Linear Stability Analysis of the Multiple Vortex Phenomenon
A Two-Dimensional Linear Stability Analysis of the Multiple Vortex Phenomenon
复制标题
多涡现象的二维线性稳定性分析
DOI：
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
R. Gall
中科院分区：
文献类型：
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作者：
R. Walko;R. Gall
本文建立了两个数值模型，研究了轴对称受迫旋转流中二次涡的形成。所研究的涡流是在实验室涡流模拟器中产生的，其中二次涡流已被产生并被广泛研究。第一个数值模型生成了一系列涡流比的稳态轴对称二维涡流。第二个模型通过模拟叠加在流动上的小振幅线性扰动的行为来测试这些流动的不稳定性：扰动的放大表示不稳定，而阻尼表示稳定。不稳定性研究的结果表明，涡流在最低涡流比时是稳定的，但在一定值以上，不稳定性无限期地持续存在。在所研究的涡流范围内，随着涡流从1增加到大约5，增长最快的波数稳定地变化。增长率被认为是足够高的f.
Abstract Two numerical models have been constructed and used to investigate the formation of secondary vortices in axisymmetrically forced rotating flows. The vortex flow examined is that developed in a laboratory vortex simulator where secondary vortices have been produced and extensively studied. The first numerical model generated a collection of steady-state, axisymmetric, two-dimensional vortex flows for a range of swirl ratios. The second model tested those flows for instability by simulating the behavior of small-amplitude, linear perturbations superimposed on the flows: amplification of the perturbations indicated instability, whereas damping indicated stability. The results of the instability study show that the vortex is stable for the lowest swirl ratios but that, above a certain value, instability persists indefinitely. The most rapidly growing wavenumber shifts steadily with increasing swirl from 1 to approximately 5 in the swirl range investigated. Growth rates were found to be high enough f...