• 全国中文核心期刊
  • 中国科技核心期刊
  • 美国工程索引(EI)收录期刊
  • Scopus数据库收录期刊
乔丽苹, 庞利磊, 王者超, 任梦梓. 岩体交叉裂隙几何特征对溶质运移的影响[J]. 岩土工程学报. DOI: 10.11779/CJGE20240134
引用本文: 乔丽苹, 庞利磊, 王者超, 任梦梓. 岩体交叉裂隙几何特征对溶质运移的影响[J]. 岩土工程学报. DOI: 10.11779/CJGE20240134
The influence of geometric characteristics of intersecting fractures in rock mass on solute transport[J]. Chinese Journal of Geotechnical Engineering. DOI: 10.11779/CJGE20240134
Citation: The influence of geometric characteristics of intersecting fractures in rock mass on solute transport[J]. Chinese Journal of Geotechnical Engineering. DOI: 10.11779/CJGE20240134

岩体交叉裂隙几何特征对溶质运移的影响

The influence of geometric characteristics of intersecting fractures in rock mass on solute transport

  • 摘要: 交叉裂隙溶质运移特征是岩体裂隙网络溶质运移的基础。对流与水动力弥散是非反应性溶质运移的主要控制机制,佩克莱数被用来评估两者在非反应性溶质运移过程中的影响占比。本文通过改变注入流体的流速,改变交叉裂隙的粗糙度、交叉角、开度比等几何特征,采用有限元数值分析获得了佩克莱数与交叉裂隙几何特征对溶质运移特性的影响规律。研究表明:随流体流速增大,溶质运移由弥散主导转向对流主导,实际工程中全面考虑弥散效应有助于准确评估交叉处溶质的混合程度;粗糙度仅影响溶质到达出口处的运移时间;交叉角、开度比通过影响溶质分子扩散到不同出口分支的概率、流体流向不同分支的方式,显著改变了交叉处的混合程度;不同流量比通过影响交叉处流向出口分支的优势流位置,影响了交叉处的混合。研究结论可为油气地下储存、垃圾填埋、核废料处置等地下工程中地下水污染物的防控治理提供理论依据。

     

    Abstract: The solute transport characteristics of intersecting fracture are the basis of solute transport in fracture network of rock mass. Advection and hydrodynamic dispersion are the main control mechanisms of non-reactive solute transport, and Péclet number is used to evaluate the proportion of influence of both on non-reactive solute transport. In this paper, by changing the flow velocity of the injected fluid, changing the geometric characteristics of the intersecting fracture, such as roughness, intersecting angle and aperture ratio, the influence of Péclet number and intersecting fracture geometric characteristics on the solute transport characteristics is obtained by finite element numerical analysis. The findings indicate that increasing flow velocity shifts solute transport from dispersion to advection. By comprehensively considering the dispersion effect in practical engineering, it is beneficial for accurately evaluating the mixing degree of solute at the intersection. Roughness primarily affects solute migration time towards outlets, while intersecting angle and aperture ratio significantly influence mixing at intersections by affecting probability of diffusion to different outlet branches and fluid flow patterns towards these branches. Different flow ratios also affect intersection mixing by influencing dominant flow positions towards exit branches. The research conclusions can provide a theoretical basis for the prevention and control of groundwater pollutants in underground engineering such as oil and gas underground storage, landfill, and nuclear waste disposal.

     

/

返回文章
返回