Varnik F, Bocquet L, Barrat J-L, Berthier L
CECAM, ENS-Lyon, 46 Allée d'Italie, 69007 Lyon, France.
Phys Rev Lett. 2003 Mar 7;90(9):095702. doi: 10.1103/PhysRevLett.90.095702. Epub 2003 Mar 3.
Using molecular dynamics simulations, we show that a simple model of a glassy material exhibits the shear localization phenomenon observed in many complex fluids. At low shear rates, the system separates into a fluidized shear band and an unsheared part. The two bands are characterized by a very different dynamics probed by a local intermediate scattering function. Furthermore, a stick-slip motion is observed at very small shear rates. Our results, which open the possibility of exploring complex rheological behavior using simulations, are compared to recent experiments on various soft glasses.
通过分子动力学模拟,我们表明,一种玻璃态材料的简单模型展现出了在许多复杂流体中观察到的剪切局部化现象。在低剪切速率下,系统分离成一个流化剪切带和一个未剪切部分。这两个带的特征是由局部中间散射函数探测到的非常不同的动力学。此外,在非常小的剪切速率下观察到了粘滑运动。我们的结果为利用模拟探索复杂流变行为开辟了可能性,并与最近对各种软玻璃的实验进行了比较。