Floquet stability analysis of capsules in viscous shear flow
Floquet stability analysis of capsules in viscous shear flow
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粘性剪切流中胶囊的流团稳定性分析
DOI：
10.1017/jfm.2018.574
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发表时间：
2018
影响因子：
3.7
通讯作者：
J. Freund
中科院分区：
文献类型：
--
作者：
Spencer H. Bryngelson;J. Freund
在实验和模拟中的观察表明，弹性胶囊的运动学行为，悬浮和旋转剪切流，取决于流动强度，胶囊膜材料的性能和它的静止形状。我们开发了一个线性稳定性描述的周期性旋转的基态的耦合系统，所代表的边界积分流公式与球谐基函数描述的弹性胶囊的几何形状。这将产生Floquet乘数，其将胶囊运动的稳定性分类为弹性毛细管数Ca$，范围为Ca=0.01$至5。粘性耗散能迅速地衰减大多数扰动。然而，对于所有的情况下，一个单一的组件增长或衰减缓慢，取决于$Ca$，在许多时期的旋转。这种稳定性行为的转变对应于在以前的研究中观察到的不同类别的旋转运动。
Observations in experiments and simulations show that the kinematic behaviour of an elastic capsule, suspended and rotating in shear flow, depends upon the flow strength, the capsule membrane material properties and its at-rest shape. We develop a linear stability description of the periodically rotating base state of this coupled system, as represented by a boundary integral flow formulation with spherical harmonic basis functions describing the elastic capsule geometry. This yields Floquet multipliers that classify the stability of the capsule motion for elastic capillary numbers $Ca$ ranging from $Ca=0.01$ to 5. Viscous dissipation rapidly damps most perturbations. However, for all cases, a single component grows or decays slowly, depending upon $Ca$ , over many periods of the rotation. The transitions in this stability behaviour correspond to the different classes of rotating motion observed in previous studies.
影响因子：
3.7
作者：
Juniper, Matthew P.
通讯作者：
Juniper, Matthew P.
影响因子：
8.6
作者：
Skotheim, J. M.;Secomb, T. W.
通讯作者：
Secomb, T. W.