非均质土柱中溶质迁移的连续时间随机游走模拟

熊云武; 黄冠华; 黄权中

非均质土柱中溶质迁移的连续时间随机游走模拟

1.
中国农业大学水利与土木工程学院, 北京, 100083
2.
中国-以色列国际农业研究培训中心, 北京, 100083

基金项目: 国家自然科学基金资助项目(50479011;50339030;50279025);教育部新世纪优秀人才支持计划(NCET-05-0125)~~

详细信息

作者简介:
熊云武(1980- ),男,重庆人,硕士研究生,主要从事水资源与水环境方面的研究.

通讯作者:
黄冠华,E-mail:ghuang@cau.edu.cn

中图分类号: P641.2
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- 文章访问数: 292
- HTML全文浏览量: 32
- PDF下载量: 711
出版历程
- 收稿日期: 2005-08-29
- 修回日期: 2005-12-27
- 刊出日期: 2006-11-24

Modeling solute transport in heterogeneous soil column using continuous time random walk

1.
College of Water Conservancy & Civil Engineering, China Agricultural University, Beijing 100083, China;
2.
Chinese-Israeli International Center for Research and Training in Agriculture, Beijing 100083, China

Funds: The study is financially supported by the National Natural Science Foundation of China(No.50479011,50339030,50279025).

摘要

摘要: 非均质介质中溶质迁移往往出现非费克现象,传统的对流弥散方程(ADE)则难以较好地描述这种现象.采用连续时间的随机游走理论(CTRW)研究1250cm长一维非均质土柱中溶质运移问题,探讨CTRW模型中参数及非费克迁移的变化特征.研究结果表明,β值的大小与介质的非均质特征有关,非均质性越强,β值越小,但β值具有相对的稳定性,然而ADE的弥散系数则具有随尺度增大而增大的现象.对于介质非均质性较强和非费克现象较明显的溶质穿透曲线,尤其是在拖尾部分,与ADE相比,CTRW具有较高的模拟精度.
- 非均质介质 /
- 连续时间随机游走 /
- 非费克现象 /
- 溶质运移
Abstract: Solute transport in heterogeneous media always occurs in the non-Fickian process with early arrival and long-tail. We analyze the data of the breakthrough curves(BTCs)measured in a 1 250 cm long heterogeneous soil column with the continuous time random walk(CTRW)and the advection-dispersion equation(ADE). It is found that Fickian behavior occurs in the transport at the distances from the inlet to 100 cm with a β value larger than 2,which is attributable to relatively homogeneous packing. Within the distances from 200 cm to 700 cm,the transport has significant non-Fickian behavior with β=0.915±0.024,this is due to the highly heterogeneity when packing the column. While the moderate non-Fickian transport isfound within the distances from 800 cm to 1200cm,and theβvalue is 1.19±0.0691 Compared with the dispersion coefficient of ADE,βvalue is relative stable. Better simulation results are also obtained especially for the tails of BTCs by using CTRW with respect to ADE. It implies that CTRW is a useful method to describe the scale-dependent transport and non-Fickian trans-port.
- heterogeneous media /
- continuous time random walk /
- non-Fickian /
- solute transport

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参考文献(26)

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文章访问数: 292
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非均质土柱中溶质迁移的连续时间随机游走模拟

作者简介: 熊云武(1980- ),男,重庆人,硕士研究生,主要从事水资源与水环境方面的研究.

通讯作者: 黄冠华,E-mail:ghuang@cau.edu.cn

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出版历程

Modeling solute transport in heterogeneous soil column using continuous time random walk

计量

出版历程

目录

作者简介:
熊云武(1980- ),男,重庆人,硕士研究生,主要从事水资源与水环境方面的研究.

通讯作者:
黄冠华,E-mail:ghuang@cau.edu.cn