Experimental observation of viscoelastic fluid-structure interactions
Experimental observation of viscoelastic fluid-structure interactions
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DOI：
10.1017/jfm.2017.15
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发表时间：
2017-02-25
影响因子：
3.7
通讯作者：
Rothstein, Jonathan P.
中科院分区：
文献类型：
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作者：
Dey, Anita A.;Modarres-Sadeghi, Yahya;Rothstein, Jonathan P.
众所周知，当柔性或柔性安装的结构垂直于牛顿流体的流动放置时，它可以由于分离的涡流的脱落而振荡。在这里，我们首次表明，流体结构的相互作用，也可以观察到当流体是粘弹性的。对于粘弹性流体，由于纯弹性流动不稳定性的开始，在无穷小的雷诺数下，在没有流体惯性的情况下，柔性结构可以变得不稳定。柔性结构的非线性周期振荡被观察到，并发现他耦合到结构的尾流中的粘弹应力的时间依赖性的增长和衰减。
It is well known that when a flexible or flexibly mounted structure is placed perpendicular to the flow of a Newtonian fluid, it can oscillate due to the shedding of separated vortices. Here, we show for the first time that fluid structure interactions can also be observed when the fluid is viscoelastic. For viscoelastic fluids, a flexible structure can become unstable in the absence of fluid inertia, at infinitesimal Reynolds numbers, due to the onset of a purely elastic flow instability. Nonlinear periodic oscillations of the flexible structure are observed and found to he coupled to the time-dependent growth and decay of viscoclastic stresses in the wake of the structure.