Transition to Versus from Turbulence in Subcritical Couette Flows
Transition to Versus from Turbulence in Subcritical Couette Flows
复制标题
亚临界库埃特流中从湍流到湍流的转变
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
O. Dauchot
中科院分区：
文献类型：
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作者：
A. Prigent;O. Dauchot
我们报告的实验进行泰勒-库埃特和平面库埃特流考虑从层流到湍流的过渡和从湍流到层流的反向过渡。在第一种情况下，过渡是不连续的，其特征在于层流-湍流共存。过渡由有限振幅解的存在控制。在第二种情况下，出乎意料的是，过渡是连续的，并导致一个周期性的条纹图案，其波长是大的剪切尺度相比。这种模式甚至可以描述在一个广义的噪声金斯堡-朗道形式主义。在这种背景下，间歇性和无序的层流-湍流共存可以被看作是湍流流动调制的最终阶段。
We report experiments conducted in Taylor—Couette and plane Couette flows considering both the transition from laminar to turbulent flow and the reverse transition from turbulent to laminar flow. In the first case, the transition is discontinuous and is characterized by laminar-turbulent coexistence. The transition is controlled by the existence of finite amplitude solutions. In the second case, unexpectedly, the transition is continuous and leads to a periodical stripes pattern whose wavelength is large compared to the shear scale. This pattern can even be described in a generalized noisy Ginzburg—Landau formalism. In this context, the intermittent and disordered laminar-turbulent coexistence can be seen as the ultimate stage of the modulation of the turbulent flows.