论文标题
通过多孔培养基模型上和通过多孔介质悬浮液的速度测量
Velocity measurements of a dilute particulate suspension over and through a porous medium model
论文作者
论文摘要
我们通过多孔培养基模型在实验中检查了1％，3％和5％稀释液的压力驱动流量。在非常低的雷诺数下，认为悬浮在牛顿液中的刚性和球形颗粒的非胶体，非棕色的悬浮液的流动。多孔介质的模型由矩形通道中流动的杆的平方阵列组成。使用高空间分辨率平面粒子图像速度（PIV）和索引匹配技术进行系统实验，以准确测量在多孔媒体模型内部和顶部非常稀释和溶剂流的速度测量。我们发现，对于1％，3％和5％的稀释悬浮液，自由流动区域内的完全发达的速度曲线可以通过将Navier-Stokes方程与自由流域内的Navier-Stokes方程构成的精确溶液进行了很好的预测，并且在自由流动区域内的Navier-Stokes方程以及体积平均的Navier Stokes（VAN）方程（VAN）方程（VAN）方程。我们进一步分析了悬浮孔界面处的速度和剪切速率，并将这些数据与纯悬浮液和相关分析溶液的数据进行比较。精确的解决方案用于定义计算钥匙值所需的参数，以分析多孔介质/流体相互作用，例如达西速度，穿透深度和质量流量的分数比。这些参数在溶剂，稀释液和精确溶液之间是可比的。但是，我们发现溶剂与悬浮液之间的明显影响，这些溶剂表现出不同的物理现象，当将颗粒引入流过多孔培养基的流中并通过多孔培养基移动时发生了不同的物理现象。
We experimentally examine pressure-driven flows of 1%, 3%, and 5% dilute suspensions over and through a porous media model. The flow of non-colloidal, non-Brownian suspensions of rigid and spherical particles suspended in a Newtonian fluid is considered at very low Reynolds numbers. The model of porous media consists of square arrays of rods oriented across the flow in a rectangular channel. Systematic experiments using high-spatial-resolution planar particle image velocimetry (PIV) and index-matching techniques are conducted to accurately measure the velocity measurements of both very dilute and solvent flows inside and on top of the porous media model. We found that for 1%, 3%, and 5% dilute suspensions the fully-developed velocity profile inside the free-flow region are well predicted by the exact solution derived from coupling the Navier-Stokes equation within the free flow-region and the volume-averaged Navier Stokes (VANS) equation for the porous media. We further analyze the velocity and shear rate at the suspension-porous interface and compare these data with those of pure suspending fluid and the related analytical solutions. The exact solution is used to define parameters necessary to calculate key values to analyze the porous media/fluid interaction such as Darcy velocity, penetration depth, and fractional ratios of the mass flow rate. These parameters are comparable between the solvent, dilute suspensions, and exact solution. However, we found clear effects between the solvent and the suspensions which shows different physical phenomenon occurring when particles are introduced into a flow moving over and through a porous media.
