Nonlocal Effects Reflect the Jamming Criticality in Frictionless Granular Flows Down Inclines.
Nonlocal Effects Reflect the Jamming Criticality in Frictionless Granular Flows Down Inclines.
复制标题
非局部效应反映了斜坡上无摩擦颗粒流的干扰临界性。
DOI：
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发表时间：
2021
影响因子：
8.6
通讯作者：
Y. Forterre
中科院分区：
文献类型：
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作者：
H. Perrin;M. Wyart;B. Metzger;Y. Forterre
干扰过渡伴随着丰富的现象学，如滞后或非局部效应，仍然没有很好地理解。在这里，我们通过实验研究了一个模型无摩擦颗粒层沿斜面流下，作为一种方式来解开摩擦相互作用所产生的一般集体效应。我们发现，薄的无摩擦颗粒层是没有滞后的雪崩角，但层的稳定性增加，因为它变得更薄。稳定流变法获得不同的层厚度可以崩溃成一个独特的主曲线，支持的想法，即非局部效应是通常的有限尺寸效应与临界点的存在相关的后果。这种坍缩表明，所谓的均衡长度l^{*}，即钉扎边界冻结所有剩余松弛模的尺度，决定了边界对流动的影响，并排除了过去提出的其他命题。
The jamming transition is accompanied by a rich phenomenology such as hysteresis or nonlocal effects that is still not well understood. Here, we experimentally investigate a model frictionless granular layer flowing down an inclined plane as a way to disentangle generic collective effects from those arising from frictional interactions. We find that thin frictionless granular layers are devoid of hysteresis of the avalanche angle, yet the layer stability increases as it gets thinner. Steady rheological laws obtained for different layer thicknesses can be collapsed into a unique master curve, supporting the idea that nonlocal effects are the consequence of the usual finite-size effects associated with the presence of a critical point. This collapse indicates that the so-called isostatic length l^{*}, the scale on which pinning a boundary freezes all remaining floppy modes, governs the effect of boundaries on flow and rules out other propositions made in the past.