| 王开丽,黄冠华.二维强非均质含水层中渗透系数空间变异对污染物迁移的影响[J].水利学报,2010,41(4): |
| 二维强非均质含水层中渗透系数空间变异对污染物迁移的影响 |
| Effect of hydraulic conductivity on contaminant transport in highly heterogeneous two-dimensional aquifers |
| |
| DOI： |
| 中文关键词: 污染物迁移 渗透系数 空间变异性 Levy 稳定分布 Monte-Carlo 数值模拟 矩分析 宏观弥散度 |
| 英文关键词: contaminant transport hydraulic conductivity spatial variability Levy-stable distribution Monte-Carlo simulation moment analysis macrodispersivity |
| 基金项目: |
|
| 摘要点击次数: 2392 |
| 全文下载次数: 335 |
| 中文摘要: |
| 对于强非均质介质，渗透系数的对数lnK 的空间分布可表征为其增量遵从Levy 稳定分布的非平稳随机场。本文利用改进的连续随机增量方法生成含水层lnK 增量具有Levy 稳定分布的统计特征的随机场;采用Monte-Carlo数值实验方法并结合MODFLOW 与MT3DMS 分别模拟研究区域内水流和溶质迁移过程，分析渗透系数强变异性对污染物浓度空间矩及宏观弥散的影响。结果表明:Levy 指数α 决定lnK 的空间分布形状，宽度参数C 则影响lnK的取值范围;污染物的质心位置与C、α 的大小无关;C 越大、α 越小，污染物形状越不规则，污染物的扩散范围越大;且α 越小，污染物具有明显的拖尾现象;纵向宏观弥散度随时间呈幂函数递增趋势。 |
| 英文摘要: |
| For the highly heterogeneous media，the logarithm hydraulic conductivity ( lnK) is considered as a non-stationary random field with its increments following a Levy-stable distribution. In this paper，the successive random additional (SRA) algorithm is used to produce the lnK field of the aquifer based on the Levy-stable distribution. A Monte-Carlo simulation，with which the MODFLOW and MT3DMS are used to simulate water flow and contaminant transport respectively，is performed to investigate the impact of highly heterogeneous properties on the spatial moments and macrodispersion of contaminant plume. Results indicate that the Levy index α is mainly responsible for the shape of lnK distribution，while the width parameter C has significant effect on the range of lnK values. As α becomes smaller，the contaminant plume shows more anomalously with a long time tailing part. It is also found that the spread of the contaminant plume increases with the increase of width parameter C，but the centroid position of the plume is basically independent of the values of parameters C and α. The longitudinal macrodispersivity is scale-dependent and increases as a power law function of time. |
|
查看全文
查看/发表评论 下载PDF阅读器 |
| 关闭 |