Gravity-driven granular flow in a silo: Characterizing local forces and rearrangements
Gravity-driven granular flow in a silo: Characterizing local forces and rearrangements
复制标题
筒仓中重力驱动的颗粒流：表征局部力和重新排列
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
K. Nordstrom
中科院分区：
文献类型：
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作者：
Emma Thackray;K. Nordstrom
虽然重力驱动的筒仓几何形状中的颗粒材料的流动可以通过Beverloo方程建模，但驱动这种流动的中尺度颗粒重排和相互作用还没有得到很好的理解。我们已经构建了一个准二维系统的双分散，毫米级的磁盘与光弹性性能，使力网络内的材料可见。该系统包含在一个亚克力盒子中，底部开口可调。我们可以通过调整这个开口来接近堵塞过渡。通过将系统放置在交叉偏振器之间，我们可以在流动期间获得该系统的高速视频，并提取可用于识别和量化局部的强度信号，否则不确定的力。我们可以同时跟踪单个粒子的运动，这可以用来识别系统中的剪切转换区。在本文中，我们提出了我们的结果到目前为止。
While the gravity-driven flow of a granular material in a silo geometry can be modeled by the Beverloo equation, the mesoscale-level particle rearrangements and interactions that drive this flow are not wellunderstood. We have constructed a quasi-two-dimensional system of bidisperse, millimeter-scale disks with photoelastic properties that make force networks within the material visible. The system is contained in an acrylic box with an adjustable bottom opening. We can approach the clogging transition by adjusting this opening. By placing the system between cross-polarizers, we can obtain high-speed video of this system during flow, and extract intensity signals that can be used to identify and quantify localized, otherwise indeterminate forces. We can simultaneously track individual particle motions, which can be used to identify shear transformation zones in the system. In this paper, we present our results thus far.