论文标题
微武器靠近波纹状，周期性表面
Microswimmers near corrugated, periodic surfaces
论文作者
论文摘要
我们探索微武器和瓦楞纸或粗糙表面之间的流体动力相互作用，如生物系统和微流体设备中经常发现。使用Lorentz倒数定理进行粘性流，我们将粗糙度诱导的速度的精确表达式得出到表面高度波动中的一阶，并为转换和角度速度提供有效的溶液，对任意表面形状有效。我们应用理论预测来阐明周期性的波浪表面对以斯托克斯奇异性的叠加为模型的微武器速度的影响。我们的发现在远场分析的框架中有效，表明粗糙度诱导的速度随表面波长而非单调的变化。对于与游泳者地面距离相当的波长，由于表面腔边缘的流场反射，推动器可以经历排斥贡献，从而减少了对墙壁的整体吸引力。
We explore hydrodynamic interactions between microswimmers and corrugated, or rough, surfaces, as found often in biological systems and microfluidic devices. Using the Lorentz reciprocal theorem for viscous flows we derive exact expressions for the roughness-induced velocities up to first order in the surface-height fluctuations and provide solutions for the translational and angular velocities valid for arbitrary surface shapes. We apply our theoretical predictions to elucidate the impact of a periodic, wavy surface on the velocities of microswimmers modeled in terms of a superposition of Stokes singularities. Our findings, valid in the framework of a far-field analysis, show that the roughness-induced velocities vary non-monotonically with the wavelength of the surface. For wavelengths comparable to the swimmer-surface distance a pusher can experience a repulsive contribution due to the reflection of flow fields at the edge of a surface cavity, which decreases the overall attraction to the wall.
