Experimental study of rotating disk flow instability. II. Forced flow
Experimental study of rotating disk flow instability. II. Forced flow
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转盘流动不稳定性实验研究。
DOI：
10.1063/1.869076
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发表时间：
1996
影响因子：
4.6
通讯作者：
M. Chauve
中科院分区：
文献类型：
--
作者：
S. Jarre;P. L. Gal;M. Chauve
本文对旋转圆盘受迫流动的失稳进行了实验研究。在横流不稳定性的线性阈值下放置一个δ阶（恒定边界层厚度）的孤立粗糙度单元，以创建一个有限振幅的流体动力学模式，并在空间中局部化。首先建立了中性稳定性实验曲线。由此产生的双抛物线曲线表现出两个极小值：其中之一是由于基模的放大，另一个是与超谐波模式的出现。通过两点测量确定的色散曲线似乎偏离了在自然情况下（无强迫）测量的色散曲线。我们发现，这种差异是由于存在弱的非线性效应，可以描述的金斯堡-朗道振幅方程。最后，我们提出了一个原始的方法，使确定两个组件的群速度矢量使用测得的色散…
The destabilization of the rotating disk flow subject to a forcing is experimentally investigated. An isolated roughness element of size of order δ (the constant boundary layer thickness) is placed under the linear threshold of the cross‐flow instability in order to create a hydrodynamic pattern of finite amplitude and localized in space. The experimental neutral stability curve is first established. The resulting double parabolic curve exhibits two minima: one of which is due to the amplification of fundamental modes, the other one is linked to the emergence of superharmonic modes. Dispersion curves determined by means of two‐point measurements appear to be shifted away from those measured in the natural case (without forcing). We show that this discrepancy is due to the presence of weak nonlinear effects which can be described by a Ginzburg–Landau amplitude equation. Lastly, we present an original method that enables to determine both components of the group velocity vector using the measured dispersion...