多孔介质水分运动的随机数值分析

采用van Genuchten-Mualem模型描述非饱和水力传导度和水分特征曲线,将模型中的3个参数作为随机场处理,联合运用Karhunen-Loeve展开和摄动方法,得到饱和非饱和水流的一个随机数值模型。应用该模型分析了介质随机参数的空间变异性对水头分布的影响,结果表明,水头标准差对介质参数的敏感程度由大到小依次为非饱和参数n、β、饱和水力传导度Ks,饱和带水头分布的变异性较非饱和带小。

Stochastic Numerical Analysis of Water Flow in Porous Media

A stochastic numerical model for saturated-unsaturated flow is developed by the combination of Karhunen-Loeve expansion and perturbation method.The van Genuchten-Mualem model is adopted to describe the unsaturated hydraulic conductivity and soil water retention curve,and the three input parameters are treated as random fields.The effect of spatial variability of random parameters on the distribution of water head is investigated with the proposed stochastic model,it is shown that the standard deviation of water head is sensitive to these variabilities in the order of unsaturated parameter n,β and saturated hydraulic conductivity K_s,and the variability of water head in saturated zone is smaller than that in unsaturated zone.