The rheology of non‐Newtonian slurries is measured in a recirculating pipe loop using an acoustic velocimetry‐pressure drop technique at very low flow rates and variable solids loadings. The technique avoids (a) settling at low solids concentration, a shortcoming of bench rheometry, by using a vertical test section, and (b) physical sampling, providing greater safety. Speed of sound in the suspensions is also modeled. In‐line and off‐line data are used to assess the suitability of several non‐Newtonian models to describe observed flow behavior. Measured and predicted values of the friction factor are compared with the Madlener et al Herschel–Bulkley extended model found to be superior. The dependence of yield stress and viscosity on solids loading and particle size is investigated, showing complexities from aggregation on the particle size distribution require more interpretation than the choice of rheological or friction‐factor model.

中文翻译：

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将管道内流变声学和摩擦系数模型扩展到低雷诺数，非牛顿泥浆

非牛顿浆液的流变特性是在循环管道回路中使用声速测压降技术在非常低的流速和可变的固体载荷下进行测量的。该技术避免了（a）通过使用垂直测试部分来解决低固体浓度，台式流变仪的缺点，以及（b）物理采样，从而提供了更高的安全性。悬架中的声音速度也已建模。在线和离线数据用于评估几种非牛顿模型来描述观察到的流动行为的适用性。将摩擦系数的测量值和预测值与发现更好的Madlener等人的Herschel-Bulkley扩展模型进行了比较。研究了屈服应力和粘度对固体含量和粒径的依赖性，