论文标题
粘性流体中不可延迟的弹性丝的数值方法
A numerical method for inextensible elastic filaments in viscous fluids
论文作者
论文摘要
鞭毛的变形在单fallage细菌的运动性中很重要。现有的数值方法将鞭毛视为具有较大伸展模量的延伸细丝，导致了严格的数值问题和较长的模拟时间。然而，鞭毛几乎是不可扩展的，因此为避免较大的延伸刚度，我们引入了不可延迟的弹性杆模型，并通过正则stokeslet的表面分布处理流体动力学。我们对以前描述的可扩展弹性杆的模型进行基准测试，该模型的流体动力学由正则化stokeslet和rotlet的中心线分布以及正则化stokeslet的表面分布进行处理。我们将不可扩展模型的准确性与可扩展模型进行了比较，并说明了伸展/弯曲刚度的比率（取决于细丝的直径），不可延迟的模型是准确，更有效的。我们表明，与许多生物丝相比，我们不可扩展的方法比可扩展的模型更为有效。我们还将Stokeslet和Rotlet的中心线分布的准确性与Stokeslet的更精确的表面分布进行比较，以建模细丝的流体结构相互作用。
The deformations of flagella are important in the motility of single- and multi-flagellated bacteria. Existing numerical methods have treated flagella as extensible filaments with a large extensional modulus, resulting in a stiff numerical problem and long simulation times. However, flagella are nearly inextensible, so to avoid large extensional stiffness, we introduce inextensible elastic rod models with hydrodynamics treated by a surface distribution of regularized Stokeslets. We benchmark this new model against previously described models of extensible elastic rods with hydrodynamics treated by a centerline distribution of regularized Stokeslets and rotlets, as well as a surface distribution of regularized Stokeslets. We compare the accuracy of the inextensible model with the extensible models and illustrate for which ratios of stretching/bending stiffness (which depend on the diameter of filament) the inextensible model is accurate and more efficient. We show that our inextensible approach can be markedly more efficient than the extensible models for many biological filaments. We also compare the accuracy of the centerline distribution of the Stokeslets and rotlets to the more accurate surface distribution of Stokeslets for modeling fluid-structure interactions of filaments.
