论文标题
边界控制主动通道流
Boundaries control active channel flows
论文作者
论文摘要
边界条件决定了当通过通道泵送时流体（包括液晶）如何流动。边界条件还可以用于控制自发产生流动的内部驱动的活性流体吗？通过使用数值模拟和稳定性分析，我们探讨了在边界和底物阻力处如何将活性药物的表面锚定用于纠正2D通道中活性极性流体的相干流动。在活动增加后，从层流到涡流阵列到最终的湍流，获得了一系列动力状态，这些态是由流体动力筛选长度与外推长度之间的相互作用所控制的，从而量化了定向阶参数参数的锚定强度。我们强调了对称性在流量和顺序中的关键作用，并表明仅对于弱锚定和中间活动才有可能具有净吞吐量的相干层流。我们的工作证明了仅通过对限制边界进行图案来控制信道中主动流的性质和特性的可能性。
Boundary conditions dictate how fluids, including liquid crystals, flow when pumped through a channel. Can boundary conditions also be used to control internally driven active fluids that generate flows spontaneously? By using numerical simulations and stability analysis we explore how surface anchoring of active agents at the boundaries and substrate drag can be used to rectify coherent flow of an active polar fluid in a 2D channel. Upon increasing activity, a succession of dynamical states is obtained, from laminar flow to vortex arrays to eventual turbulence, that are controlled by the interplay between the hydrodynamic screening length and the extrapolation length quantifying the anchoring strength of the orientational order parameter. We highlight the key role of symmetry in both flow and order and show that coherent laminar flow with net throughput is only possible for weak anchoring and intermediate activity. Our work demonstrates the possibility of controlling the nature and properties of active flows in a channel simply by patterning the confining boundaries.
