Pore Network Drying Model for Particle Aggregates: Assessment by X-Ray Microtomography
Pore Network Drying Model for Particle Aggregates: Assessment by X-Ray Microtomography
复制标题
DOI：
10.1080/07373937.2012.713422
复制
发表时间：
2012-11
影响因子：
3.3
通讯作者：
Yujing Wang;A. Kharaghani;T. Metzger;E. Tsotsas
中科院分区：
文献类型：
--
作者：
Yujing Wang;A. Kharaghani;T. Metzger;E. Tsotsas
对无序玻璃珠填料的对流干燥进行了实验和数值研究。X射线显微断层扫描（XMT）和图像分析技术已被用来确定在湿颗粒聚集体内的孔隙尺度的液相和固相的三维空间分布。在干燥过程中，已经跟踪了骨料中液体分布的演变。利用二值化和分割技术从X射线图像中提取了粒子中心坐标和半径。基于该真实的聚集体的几何数据，通过将Voronoi边缘指定为具有从相邻颗粒之间的距离计算的半径的互连圆柱形孔，已经从关于颗粒中心的Voronoi镶嵌（tessellation）生成了孔隙空间的孔隙网络近似。这种三维不规则孔隙网络考虑了实际孔隙空间的几何和拓扑特征（孔径分布和连通性）。干燥模拟已经进行了从XMT获得的孔隙网络和结果呈现为相分布和水分分布。模拟的液相分布与实验结果定性一致，表明孔网络模型适合描述孔尺度下的致密颗粒团聚体干燥过程。
Convective drying of disordered glass bead packings has been investigated both experimentally and numerically. X-ray microtomography (XMT) and image analysis techniques have been used to determine the three-dimensional spatial distribution of the liquid and solid phases at the pore scale within the wet particle aggregates. The evolution of the liquid distribution in the aggregate has been tracked during the drying process. Particle center coordinates and radii have been extracted from the X-ray images using binarization and segmentation techniques. Based on this geometric data for a real aggregate, a pore network approximation of the pore space has been generated from a Voronoi tessellation about particle centers by designating Voronoi edges as interconnected cylindrical pores with radii computed from the distance between neighboring particles. This three-dimensional irregular pore network takes into account both the geometrical and topological characteristics (pore size distribution and connectivity) of the actual pore space. Drying simulations have been carried out for the pore networks obtained from the XMT and results are presented as phase distributions and moisture profiles. The simulated liquid phase distributions are in qualitative agreement with the experimental result, which indicates that pore network models are suited to describe the drying of dense particle aggregates at the pore scale.