Experimental Measurement of Macropore Flow in Porous Media

这项研究将测量和量化流动的水力学， 土壤大孔隙及大孔隙与土壤的相互作用 周围的多孔介质。 一种非破坏性伽马射线层析成像， 单位将用于获得水含量分布， 在流动事件期间，实验室色谱柱的分辨率为5 mm， 再分布后2 mm。 将测试多种孔隙类型 其尺寸和形成方法不同。 这些直接 土壤水分时空变化的测量 内容将允许计算流量水力学。 那些 结果将反过来，比较现有的确定性 大孔隙流动理论 具体假设将 评价的是：1）大孔内的泊松流，2） 孔隙与周围孔隙的水力平衡 介质，3）模拟水的径向吸附的适用性 从孔隙正常水平吸附，和4）的影响， 表面密封水进入孔隙的入口。

This research will measure and quantify the hydraulics of flow in soil macropores and the interactions between macropores and the surrounding porous media. A non-destructive gamma ray tomography unit will be used to obtain water content distributions in laboratory columns to a resolution of 5 mm during flow events and 2 mm after redistribution. A variety of pore types will be tested which will differ in size and method of formation. These direct measurements of the temporal and spatially varying soil water content will allow the calculation of flow hydraulics. Those results will in turn, be compared to existing deterministic theories of macropore flow. Specific assumptions which will be evaluated are; 1) poiseuille flow within the macropore, 2) hydraulic equilibrium between the pore and the surrounding porous media, 3) the suitability of modeling the radial sorption of water from the pore as normal horizontal sorption, and 4) the effects of surface seals on the entrance of water into the pore.