Predicting Hydraulic Properties from Pressure-Saturation Curves

压力-饱和度曲线揭示了多孔介质中孔隙大小分布的信息，但由于滞后和缺乏平衡，这些数据的解释可能会很复杂。在干燥条件下，缺乏平衡通常是低水力导电性K的结果。低K值可以在渗流理论的框架内预测，使用一个一般的结果，即随着饱和度的降低，流动从孔隙大小主导（关键路径分析）过渡到连通性主导（渗流标度）。虽然这种分析已经对一种特定形式的孔径分布（分形）进行了分析，但拟议的工作将使用任意持水曲线作为输入进行一般（数值）分析。自一致的程序解释了在低水分含量下脱离平衡的并发症。输出为孔径分布和水力导率。来自部分颗粒尺寸分布的补充输入将进一步确认孔径分布，也可用于计算比表面积，这与渗透的临界水分含量有关。

Hunt 0609884Pressure-saturation curves reveal information about the pore size distribution in porous media, but interpretation of these data can be complicated through hysteresis and lack of equilibration. Lack of equilibration is often a consequence of low hydraulic conductivity, K, under dry conditions. Low values of K can be predicted within the framework of percolation theory using a general result that as saturation is reduced flow crosses over from pore-size dominated (critical path analysis) to connectivity dominated (percolation scaling). Although this analysis was already performed analytically for a particular form of the pore size distribution (fractal) the proposed work will perform general (numerical) analysis using an arbitrary water retention curve as input. A self-consistent procedure accounts for complications from falling out of equilibrium at low moisture contents. The outputs are the pore-size distribution and the hydraulic conductivity. Supplemental inputs from part icle size distributions will give additional confirmation of the pore size distribution and also be used for calculation of the specific surface area, which is relevant to the critical moisture content for percolation.