Wortel Geert H, van Hecke Martin
Huygens-Kamerlingh Onnes Lab, Universiteit Leiden, Postbus 9504, 2300 RA Leiden, The Netherlands.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Oct;92(4):040201. doi: 10.1103/PhysRevE.92.040201. Epub 2015 Oct 28.
We experimentally probe the anisotropy of weakly vibrated flowing granular media. Depending on the driving parameters-flow rate and vibration strength-this anisotropy varies significantly. We show how the anisotropy collapses when plotted as a function of the driving stresses, uncovering a direct link between stresses and anisotropy. Moreover, our data suggest that for small anisotropies, the shear stresses vanish. Anisotropy of the fabric of granular media thus plays a crucial role in determining the rheology of granular flows.
我们通过实验探究了弱振动流动颗粒介质的各向异性。根据驱动参数——流速和振动强度——这种各向异性会有显著变化。我们展示了将各向异性作为驱动应力的函数绘制时，它是如何消失的，揭示了应力与各向异性之间的直接联系。此外，我们的数据表明，对于小的各向异性，剪应力会消失。因此，颗粒介质结构的各向异性在确定颗粒流的流变学方面起着关键作用。
