论文标题
三球游泳运动员的化学感受和趋化性
Chemoreception and chemotaxis of a three-sphere swimmer
论文作者
论文摘要
研究了Najafi-Golestanian三球游泳运动员的流体力学和溶质传输问题，雷诺数将零数设置为零，而Péclet编号（PE）为0.06至60。所采用的方法是基于Fenics库的有限元代码的数值仿真。对于执行最佳运动步态的游泳者，我们报告了舍伍德的数量是PE在同质流体中的函数，并确认通过游泳的溶质通量几乎没有增长，除非PE明显大于10。 Q学习过程的结果表明，学习运动（以奖励为奖励）要比学习趋化性（随着溶质通量作为奖励的增加）要容易得多。趋化问题即使在低PE处，也具有不同的环境，使学习更加困难。此外，学习难度随着Péclet数量的严重增加。结果表明，自然和人工游泳者需要克服的挑战以在暴露于化学不均匀性时有效迁移。
The coupled problem of hydrodynamics and solute transport for the Najafi-Golestanian three-sphere swimmer is studied, with the Reynolds number set to zero and Péclet numbers (Pe) ranging from 0.06 to 60. The adopted method is the numerical simulation of the problem with a finite element code based upon the FEniCS library. For the swimmer executing the optimal locomotion gait, we report the Sherwood number as a function of Pe in homogeneous fluids and confirm that little gain in solute flux is achieved by swimming unless Pe is significantly larger than 10. We also consider the swimmer as an learning agent moving inside a fluid that has a concentration gradient. The outcomes of Q-learning processes show that learning locomotion (with the displacement as reward) is significantly easier than learning chemotaxis (with the increase of solute flux as reward). The chemotaxis problem, even at low Pe, has a varying environment that renders learning more difficult. Further, the learning difficulty increases severely with the Péclet number. The results demonstrate the challenges that natural and artificial swimmers need to overcome to migrate efficiently when exposed to chemical inhomogeneities.
