论文标题
孔网络模型预测流体流并拖动饱和颗粒材料的能力
Ability of a pore network model to predict fluid flow and drag in saturated granular materials
论文作者
论文摘要
将来自孔网络模型（PNM）获得的局部流场和渗漏诱导的阻力与浸入式边界方法（IBM）模拟进行了比较，以范围为一系列线性分级和双峰样品。使用加权的Delaunay Tessellation（DT）以及修改后的Delaunay Tessellation（MDT）生成PNM，该Teshellation（MDT）考虑了四面体Delaunay细胞的合并。在所有线性分级和双峰样品中都非常准确地捕获了局部压力场。局部通量（流速）表现出更多的散射，但是基于MDT的PNM显然提供了与IBM更好的相关性。从PNM和IBM获得的网络最短路径的相似性，表明PNM捕获了主要的流动通道。此外，通过将PNM覆盖在流线轮廓上，可以证明局部压力下降与孔隙收缩相吻合。通过与有序的球体阵列进行比较，对从PNM计算出的阻力进行了严格的验证。随后将该方法应用于所有线性分级和双峰样品，并将计算的力与IBM数据进行了比较。线性渐变样品能够以合理的精度计算力，而双峰样品表现出散射稍高。
The local flow field and seepage induced drag obtained from Pore Network Models (PNM) is compared to Immersed Boundary Method (IBM) simulations, for a range of linear graded and bimodal samples. PNM were generated using a weighted Delaunay Tessellation (DT), along with the Modified Delaunay Tessellation (MDT) which considers the merging of tetrahedral Delaunay cells. The local pressure field was very accurately captured in all linear graded and bimodal samples. Local flux (flow rate) exhibited more scatter, but the PNM based on the MDT clearly provided a better correlation with the IBM. There was close similarity in the network shortest paths obtained from PNM and IBM, indicating that the PNM captures dominant flow channels. Further, by overlaying the PNM on a streamline profile, it was demonstrated that local pressure drops coincided with the pore constrictions. A rigorous validation was undertaken for the drag force calculated from the PNM by comparing with analytical solutions for ordered array of spheres. This method was subsequently applied to all linear graded and bimodal samples, and the calculated force was compared with the IBM data. Linear graded samples were able to calculate the force with reasonable accuracy, while the bimodal sample exhibited slightly more scatter.
