A novel rheometer to study the behavior of granular materials in an aerated bed of particles has been developed. The device, called the aerated bed virtual Couette rheometer, is shown to be able to measure the shear stresses in the quasi‐static and in the intermediate flow regimes. To validate the instrument, a Newtonian fluid of known viscosity was first sheared. The device was then used for measuring the shear stress of nonaerated glass beads with three ‐3D printed cells of different sizes to validate the optimal radial position, r*, where both shear rate and shear stress are independent of the cell radius. The results for the nonaerated glass beads displayed Coulomb behavior. The same behavior was observed when the bed was aerated. These experiments also showed that for a fixed shear rate the shear stress decreases as the aeration velocity, U. increases.

中文翻译：

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开发用于充气颗粒物料的虚拟Couette流变仪

已经开发了一种新颖的流变仪，用于研究颗粒在充气颗粒床中的行为。该设备被称为充气床虚拟库埃特流变仪，被证明能够在准静态和中间流动状态下测量切应力。为了验证该仪器，首先剪切了已知粘度的牛顿流体。然后将该设备用于测量带有三个大小不同的三个‐3D打印单元的未充气玻璃珠的剪切应力，以验证最佳径向位置r*，其中剪切速率和剪切应力均与单元半径无关。未充气玻璃珠的结果显示出库仑行为。充气床时观察到相同的行为。这些实验还表明，对于固定的剪切速率，剪切应力随着通气速度U的降低而减小。增加。