分形法估算分散性污染物的运移时间

Fractal travel time estimates for dispersive contaminants

污染物运移的分形模型导出一个新的适于任意浓度的污染物运移时间公式。对于一个高度非均质含水层中逐渐形成的污染羽,新公式预算出低浓度更早到达的测点。污染峰或羽的运移时间一般经常从达西定律中采用估算平均孔隙流速法得到,而此估算仅仅提供平均浓度(或污染脉冲的峰值浓度)的运移时间信息。近来,计算出任意浓度的运移时间是一个很直接的过程,并且对一个无反应污染物而言,其突破曲线部分的方程被发展。在文中,我们推导出这些方程去概括污染物运移的分形模型。

Alternative fractional models of contaminant transport lead to a new travel time formula for arbitrary concentration levels, For an evolving contaminant plume in a highly heterogeneous aquifer, the new formula predicts much earlier arrival at low concentrations. Travel times of contaminant fronts and plumes are often obtained from Darcy＇s law calculations using estimates of average pore velocities. These estimates only provide information about the travel time of the average concentration （or peak, for contaminant pulses）. Recently, it has been shown that finding the travel times of arbitrary concentration levels is a straightforward process, and equations were developed for other portions of the breakthrough curve for a nonreactive contaminant. In this paper, we generalize those equations to include alternative fractional models of contaminant transport.