Dilatancy, jamming, and the physics of granulation
Dilatancy, jamming, and the physics of granulation
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膨胀、干扰和造粒物理学
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
C. Holmes
中科院分区：
文献类型：
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作者：
M. Cates;M. Haw;C. Holmes
造粒是一个过程，其中一个密集的胶体悬浮液转化为糊状颗粒（被空气包围）通过应用剪切。颗粒稳定性的核心是由溶剂和空气之间的界面张力引起的毛细力。在相同数量的溶剂和胶体也可以作为可流动的液滴存在的条件下，这种力似乎能够使颗粒保持在堵塞的固体状态。我们认为，在造粒的早期阶段，膨胀的物理，这要求粉末在剪切时膨胀，被毛细力转化为阻滞的物理。利用应力下胶体阻滞的示意图模型，我们推测了各种干扰和造粒情景。本文还介绍了硬球胶体悬浮液造粒方面的一些初步实验结果。
Granulation is a process whereby a dense colloidal suspension is converted into pasty granules (surrounded by air) by application of shear. Central to the stability of the granules is the capillary force arising from the interfacial tension between solvent and air. This force appears capable of maintaining a granule in a jammed solid state, under conditions where the same amount of solvent and colloid could also exist as a flowable droplet. We argue that in the early stages of granulation the physics of dilatancy, which requires that a powder expand on shearing, is converted by capillary forces into the physics of arrest. Using a schematic model of colloidal arrest under stress, we speculate upon various jamming and granulation scenarios. Some preliminary experimental results on aspects of granulation in hard-sphere colloidal suspensions are also presented.