Reichert M, Stark H
Fachbereich Physik, Universität Konstanz, D-78457 Konstanz, Germany.
Eur Phys J E Soft Matter. 2005 Aug;17(4):493-500. doi: 10.1140/epje/i2004-10152-7. Epub 2005 Aug 11.
Some types of bacteria use rotating helical flagella to swim. The motion of such organisms takes place in the regime of low Reynolds numbers where viscous effects dominate and where the dynamics is governed by hydrodynamic interactions. Typically, rotating flagella form bundles, which means that their rotation is synchronized. The aim of this study is to investigate whether hydrodynamic interactions can be at the origin of such a bundling and synchronization. We consider two stiff helices that are modelled by rigidly connected beads, neglecting any elastic deformations. They are driven by constant and equal torques, and they are fixed in space by anchoring their terminal beads in harmonic traps. We observe that, for finite trap strength, hydrodynamic interactions do indeed synchronize the helix rotations. The speed of phase synchronization decreases with increasing trap stiffness. In the limit of infinite trap stiffness, the speed is zero and the helices do not synchronize.
某些种类的细菌利用旋转的螺旋鞭毛游动。这类生物体的运动发生在低雷诺数 regime 中，其中粘性效应占主导，且动力学由流体动力相互作用支配。通常，旋转的鞭毛会形成束状，这意味着它们的旋转是同步的。本研究的目的是探究流体动力相互作用是否可能是这种成束和同步的起源。我们考虑由刚性连接的珠子建模的两个刚性螺旋，忽略任何弹性变形。它们由恒定且相等的扭矩驱动，并通过将其末端珠子固定在谐波陷阱中来固定在空间中。我们观察到，对于有限的陷阱强度，流体动力相互作用确实会使螺旋旋转同步。相位同步的速度随着陷阱刚度的增加而降低。在无限陷阱刚度的极限情况下，速度为零，螺旋不同步。
