论文标题
柔软的头发组合的集体僵硬
Collective stiffening of soft hair assemblies
论文作者
论文摘要
许多生活系统都使用柔软和细长结构的组件，这些结构的偏转使它们能够机械地探测其直接环境。在这项工作中，我们通过成像偏转来研究人造软发组件对剪切流的集体响应。在所有毛发上，发现挠度与局部剪切应力成正比，比例因子随密度降低。测得的头发集体僵硬既是使用微观弹性水力动力学模型建模的，该模型考虑了远距离水动力毛发相互作用和现象学模型，将头发组装视为有效的多孔培养基。尽管微观模型与低头发密度下的实验合理一致，但发现现象学模型在整个密度范围内具有预测性。
Many living systems use assemblies of soft and slender structures whose deflections allow them to mechanically probe their immediate environment. In this work, we study the collective response of artificial soft hair assemblies to a shear flow by imaging their deflections. At all hair densities, the deflection is found to be proportional to the local shear stress with a proportionality factor that decreases with density. The measured collective stiffening of hairs is modeled both with a microscopic elastohydrodynamic model that takes into account long range hydrodynamic hair-hair interactions and a phenomenological model that treats the hair assemblies as an effective porous medium. While the microscopic model is in reasonable agreement with the experiments at low hair density, the phenomenological model is found to be predictive across the entire density range.
