Musacchio Stefano, Cencini Massimo, Plan Emmanuel L C Vi M, Vincenzi Dario
Université Côte d'Azur, CNRS, LJAD, Nice, France.
Istituto dei Sistemi Complessi, CNR, via dei Taurini 19, 00185, Roma, Italy.
Eur Phys J E Soft Matter. 2018 Jul 11;41(7):84. doi: 10.1140/epje/i2018-11692-9.
We study the mixing of a passive scalar field dispersed in a solution of rodlike polymers in two dimensions, by means of numerical simulations of a rheological model for the polymer solution. The flow is driven by a parallel sinusoidal force (Kolmogorov flow). Although the Reynolds number is lower than the critical value for inertial instabilities, the rotational dynamics of the polymers generates a chaotic flow similar to the so-called elastic-turbulence regime observed in extensible polymer solutions. The temporal decay of the variance of the scalar field and its gradients shows that this chaotic flow strongly enhances mixing.
我们通过对聚合物溶液流变模型进行数值模拟，研究了二维空间中分散在棒状聚合物溶液里的被动标量场的混合情况。流动由平行正弦力（柯尔莫哥洛夫流）驱动。尽管雷诺数低于惯性不稳定性的临界值，但聚合物的旋转动力学产生了一种类似于在可拉伸聚合物溶液中观察到的所谓弹性湍流 regime 的混沌流动。标量场及其梯度方差的时间衰减表明，这种混沌流动极大地增强了混合。
