Granular suspensions present a transition from a Newtonian rheology in the Stokes limit to a Bagnoldian rheology when inertia is increased. A custom rheometer that can be run in a pressure- or a volume-imposed mode is used to examine this transition in the dense regime close to jamming. By varying systematically the interstitial fluid, shear rate, and packing fraction in volume-imposed measurements, we show that the transition takes place at a Stokes number of 10 independent of the packing fraction. Using pressure-imposed rheometry, we investigate whether the inertial and viscous regimes can be unified as a function of a single dimensionless number based on stress additivity.

中文翻译：

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浓密颗粒悬浮液中的粘性到惯性的转变

当惯性增加时，颗粒悬浮液呈现出从斯托克斯极限下的牛顿流变学到巴尼奥尔流变学的转变。可以在压力或体积施加模式下运行的定制流变仪用于检查接近堵塞的密集区域中的这种转变。通过系统地改变体积施加测量中的间质液、剪切速率和堆积分数，我们表明转变发生在斯托克斯数为 10 时，与堆积分数无关。使用压力流变测定法，我们研究了惯性和粘性状态是否可以统一为基于应力可加性的单个无量纲数的函数。