标题： 流体-胶体相互作用对非理想流体中热泳微游动器迁移率的影响 显示英文标题

标题： Effect of fluid-colloid interactions on the mobility of a thermophoretic microswimmer in non-ideal fluids

摘要： 由光驱动的Janus胶体，例如热泳粒子，作为人工微游泳器展现出有前途的前景。 然而，它们的游泳行为及其对流体特性和胶体-流体相互作用的依赖性仍知之甚少。 在此，我们使用数值模拟研究了热泳Janus胶体在其自身温度梯度中的行为。 采用具有能量守恒的耗散粒子动力学方法，研究了不同胶体-流体相互作用、边界条件和温度控制策略下非理想和理想气体状流体中的行为。 胶体-流体相互作用似乎对胶体行为有显著影响，因为它们直接影响胶体表面与流体之间的热量交换。 模拟结果表明，胶体-流体界面处的热量交换减少会导致胶体热泳迁移率的增强。 发现胶体在非理想和理想流体中的行为不同，这表明流体的可压缩性起着重要作用。 发现胶体表面周围的流场主要由源偶极子主导，这与最近的理论和模拟预测一致。 最后，不同的温度控制策略似乎对胶体的游泳速度没有显著影响。 显示英文摘要

摘要： Janus colloids propelled by light, e.g., thermophoretic particles, offer promising prospects as artificial microswimmers. However, their swimming behavior and its dependence on fluid properties and fluid-colloid interactions remain poorly understood. Here, we investigate the behavior of a thermophoretic Janus colloid in its own temperature gradient using numerical simulations. The dissipative particle dynamics method with energy conservation is used to investigate the behavior in non-ideal and ideal-gas like fluids for different fluid-colloid interactions, boundary conditions, and temperature-controlling strategies. The fluid-colloid interactions appear to have a strong effect on the colloid behavior, since they directly affect heat exchange between the colloid surface and the fluid. The simulation results show that a reduction of the heat exchange at the fluid-colloid interface leads to an enhancement of colloid's thermophoretic mobility. The colloid behavior is found to be different in non-ideal and ideal fluids, suggesting that fluid compressibility plays a significant role. The flow field around the colloid surface is found to be dominated by a source-dipole, in agreement with the recent theoretical and simulation predictions. Finally, different temperature-control strategies do not appear to have a strong effect on the colloid's swimming velocity.