Permeability of anisotropic tube pumice: Model calculations and measurements
Permeability of anisotropic tube pumice: Model calculations and measurements
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DOI：
10.1029/2006gl027224
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发表时间：
2006-09
影响因子：
5.2
通讯作者：
H. Wright;J. Roberts;K. Cashman
中科院分区：
文献类型：
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作者：
H. Wright;J. Roberts;K. Cashman
我们研究渗透流通过多孔材料使用火山火山碎屑与简单的孔隙几何形状。通过三维同步加速器X射线显微断层图像进行的层流晶格玻尔兹曼（LB）流体流动模拟使我们能够模拟通过各向异性浮石火山样品（管浮石）的流体流动。我们发现一个很好的对应关系计算的渗透性（使用简单的近似和LB模拟）和最大的实验室渗透率测量平行于大多数管浮石样品中的囊泡伸长的方向。此外，这种比较表明，小泡控制流体流动通过管浮石的孔结构，即使当大的，但孤立的，囊泡存在。然而，无论是简单的近似值，也不是LB模型的流动通过小层析体积可以充分模拟渗透流垂直于囊泡伸长或在材料具有复杂的几何形状。这种不匹配说明了当前X射线断层扫描对精细浮石结构的分辨率的限制，并显示了LB计算中尺度的重要性。
We examine permeable flow through porous materials using volcanic pyroclasts with simple pore geometries. Laminar lattice‐Boltzmann (LB) fluid flow simulations through 3‐D synchrotron x‐ray microtomographic images allow us to model fluid flow through anisotropic pumiceous volcanic samples (tube pumice). We find a good correspondence between calculated permeability (using both simple approximations and LB simulations) and maximum laboratory permeability measured parallel to the direction of vesicle elongation in most tube pumice samples. Moreover, this comparison demonstrates that small vesicles control fluid flow through the pore structure of tube pumice, even when large, but isolated, vesicles are present. However, neither simple approximations nor LB models for flow through small tomographic volumes can adequately model permeable flow perpendicular to vesicle elongation or in material with complex geometries. This mismatch illustrates current limitations in both resolution of x‐ray tomography for delicate pumice structures and shows the importance of scale in LB calculations.