论文标题
手性活性颗粒在Poiseuille流中的扩散
Diffusion of chiral active particles in a Poiseuille flow
论文作者
论文摘要
我们研究了带有poiseuille流动的二维微通道中手性活性（自螺旋体）布朗颗粒的扩散行为。使用数值模拟，我们表明颗粒的传输系数的行为，例如，平均速度$ v $和有效的扩散系数$ d_ {eff} $，很大程度上取决于流动强度$ u_0 $，翻译扩散常数$ d_0 $，d_0 $，rot rotationald_θ$d_θ$和chire $ gypiment ostim ost chire $ nimptime nypime nestime nestime nyperty $ cypime nypime nestime nyprets $ gestiment $ compity nyprets $之间。已经证明，对于$ u_0 $，$d_θ$和$ω$的最佳参数值，粒子可以表现出上游漂移，导致负$ v $。有趣的是，可以通过调整这些参数来控制$ v $的方向。我们观察到，对于$ u_0 $和$ω$的一些最佳值，在通道墙附近聚集了手性粒子，并且增强了相应的$ d_ {eff} $。但是，对于非手续粒子（$ω= 0 $），$ d_ {eff} $被Poiseuille流的存在抑制。可以预期，这些发现具有开发微流体和实验室芯片设备来分离活性颗粒的巨大潜力。
We study the diffusive behavior of chiral active (self-propelled) Brownian particles in a two-dimensional microchannel with a Poiseuille flow. Using numerical simulations, we show that the behavior of the transport coefficients of particles, for example, the average velocity $v$ and the effective diffusion coefficient $D_{eff}$, strongly depends on flow strength $u_0$, translational diffusion constant $D_0$, rotational diffusion rate $D_θ$, and chirality of the active particles $Ω$. It is demonstrated that the particles can exhibit upstream drift, resulting in a negative $v$, for the optimal parameter values of $u_0$, $D_θ$, and $Ω$. Interestingly, the direction of $v$ can be controlled by tuning these parameters. We observe that for some optimal values of $u_0$ and $Ω$, the chiral particles aggregate near a channel wall, and the corresponding $D_{eff}$ is enhanced. However, for the nonchiral particles ($Ω= 0$), the $D_{eff}$ is suppressed by the presence of Poiseuille flow. It is expected that these findings have a great potential for developing microfluidic and lab-on-a-chip devices for separating the active particles.
