Purely elastic linear instabilities in parallel shear flows with free-slip boundary conditions
Purely elastic linear instabilities in parallel shear flows with free-slip boundary conditions
复制标题
具有自由滑移边界条件的平行剪切流中的纯弹性线性不稳定性
DOI：
10.1017/jfm.2021.840
复制
发表时间：
2021
影响因子：
3.7
通讯作者：
A. Morozov
中科院分区：
文献类型：
--
作者：
Martin Lellep;M. Linkmann;B. Eckhardt;A. Morozov
摘要本文对具有自由滑移边界条件的粘弹性平面Couette流和平面Poiseuille流进行了线性稳定性分析。流体用oldyd - b本构模型描述，流动由合适的体力驱动。我们发现两种类型的流动都变得线性不稳定，并且我们描述了不稳定模态的空间结构。通过从自由滑移边界到无滑移边界的边界条件同伦，我们证明了不稳定模态与无滑移问题的最小稳定模态直接相关，在自由滑移情况下是不稳定的。我们讨论了如何将我们的观察结果用于研究最近发现的平行剪切流中的纯弹性湍流。
Abstract We perform a linear stability analysis of viscoelastic plane Couette and plane Poiseuille flows with free-slip boundary conditions. The fluid is described by the Oldroyd-B constitutive model, and the flows are driven by a suitable body force. We find that both types of flow become linearly unstable, and we characterise the spatial structure of the unstable modes. By performing a boundary condition homotopy from the free-slip to no-slip boundaries, we demonstrate that the unstable modes are directly related to the least stable modes of the no-slip problem, destabilised under the free-slip situation. We discuss how our observations can be used to study recently discovered purely elastic turbulence in parallel shear flows.
影响因子：
4.6
作者：
Dubief, Yves;Terrapon, Vincent E.;Soria, Julio
通讯作者：
Soria, Julio
DOI：
10.1073/pnas.1219666110
发表时间：
2012-12
期刊：
Proceedings of the National Academy of Sciences
影响因子：
--
作者：
D. Samanta;Y. Dubief;M. Holzner;C. Schäfer;A. Morozov;C. Wagner;B. Hof
通讯作者：
D. Samanta;Y. Dubief;M. Holzner;C. Schäfer;A. Morozov;C. Wagner;B. Hof