论文标题
手性Janus颗粒在对流卷中的扩散
Diffusion of Chiral Janus Particles in Convection Rolls
论文作者
论文摘要
通过广泛的数值模拟研究了人造活性粒子在固定对流细胞的二维周期性模式中的扩散。在较大的péclet数字的限制中，即对于低于特定含量阈值和弱旋转翻译波动的自我推广速度，该粒子经历渐近正常扩散，扩散与零流动处扩散常数的平方根的扩散恒定。通过可调式扭矩模拟的推进机制中的手性效应有利于粒子在相邻对流卷之间跳跃。滚动跳跃由多余的扩散峰发出信号，该峰似乎可以将低性和高性质的两个不同的主动扩散状态分开。我们对我们的仿真结果的定性解释是迈向对该现象进行全面分析研究的第一步。
The diffusion of an artificial active particle in a two-dimensional periodic pattern of stationary convection cells is investigated by means of extensive numerical simulations. In the limit of large Péclet numbers, i.e., for self-propulsion speeds below a certain depinning threshold and weak roto-translational fluctuations, the particle undergoes asymptotic normal diffusion with diffusion constant proportional to the square root of its diffusion constant at zero flow. Chirality effects in the propulsion mechanism, modeled here by a tunable applied torque, favors particle's jumping between adjacent convection rolls. Roll jumping is signaled by an excess diffusion peak, which appears to separate two distinct active diffusion regimes for low and high chirality. A qualitative interpretation of our simulation results is proposed as a first step toward a fully analytical study of this phenomenon.
