【090506随机建模专题翻译】之一 An Evaluation of the Active Fracture Concept in... [复制链接]

Title:
An Evaluation of the Active Fracture Concept in Modeling Unsaturated Flow and Transport in a Fractured Meter-Sized Block of Rock

Abstract:
Numerical simulation is an effective and economical method for optimally designing laboratory experiments and deriving practical experimental conditions. We executed a detailed numerical simulation study to examine the active fracture concept (AFC) using a 1-m³-sized block model. The numerical simulations for this study were performed by applying various experimental conditions, including different bottom flow boundaries, varying injection rates, and different fracture–matrix interaction (i.e., by increasing absolute matrix permeability at the fracture–matrix boundary) for a larger fracture interaction under transient or balanced-state flow regimes. Two conceptual block models were developed based on different numerical approaches: a two-dimensional discrete-fracture-network model (DFNM) and a one-dimensional dual-continuum model (DCM). The DFNM was used as a surrogate for a natural block to produce synthetic breakthrough curves of water and tracer concentration under transient or balanced-state conditions. The DCM is the approach typically used for the Yucca Mountain Project because of its computational efficiency. The AFC was incorporated into the DCM to capture heterogeneous flow patterns that occur in unsaturated fractured rocks. The simulation results from the DCM were compared with the results from the DFNM to determine whether the DCM could predict the water flow and tracer transport observed in the DFNM at the scale of the experiment. It was found that implementing the AFC in the DCM improved the prediction of unsaturated flow and that the flow and transport experiments with low injection rates in the DFNM compared better with the AFC implemented DCM at the 1-m³ scale. However, the estimated AFC parameter varied from 0.38 to 1.0 with different flow conditions, suggesting that the AFC parameter was not sufficient to fully capture the complexity of the flow processes in a 1-m³ discrete fracture network.

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链接：http://vzj.geoscienceworld.org/cgi/content/abstract/5/1/1

冷场啊，^_^

我来占个位置，总要有人来支持。不能冷场阿。以前没大看清楚这个活动的内容阿，可能难度太大，果友们研究的方向比较杂的原因吧。

我来翻译了，可能不到位，大家来讨论阿

                  米级尺度上有效裂缝概念在模拟未饱和流动和运移的评价

摘要：数值模拟技术一种优化实验设计以及获得实际实验条件的有效并且经济的方法。我们运行了一个详细的数值模拟来验证米级尺寸岩石模型上有效裂缝的概念。这项数值模拟采用了不同的实验条件包括应用不同的井底流动边界，不同的注入速度、不同的裂缝基质作用（例如通过增加裂缝－基质边界上基质的绝对渗透率）来得到紊流或者稳定流态下较大的裂缝作用效果。基于不同的数值方法发展了两种不同的岩石概念模型：一个是二维的离散裂缝网络模型另一个是一维的双重介质模型。DFNM模型用来作为天然裂缝岩石在稳态和非稳态条件下得水或者示踪剂突破曲线的一个替代品。双重介质模型主要用来模拟Yucca Mountain项目因为他具有好的计算能力。将AFC的概念融合到双重介质模型中来捕捉在未饱和裂缝岩石中的非均质流动模式。把双重介质模拟计算的结果和DFNM计算的结果进行对比来确定双重介质模型是否可以预测实验尺度上的水与示踪剂的流动和传质运动。结果发现，在DCM中引入AFC的概念改善了未饱和裂缝流动的描述精度尤其在低的注入速度下。然而，针对不同的流动条件估计的AFC参数从0.38到1.0不等，表明了AFC参数对于完全捕捉1立方米尺度上离散裂缝网络模型过程中仍然是不充分的。