中文摘要：

重非水相流体（DNAPL）在地下介质中的运移分布受多种因素影响,包括DNAPLs的物化性质、泄漏速率、地下水流速、介质非均质性等。本文基于T2VOC程序对DNAPLs在非均质地层（含低渗透性夹层）中的迁移和分布特征进行了数值模拟,分别采用三相毛管压力函数Parker模型和二相毛管压力函数van Genuchten模型,研究了夹层的饱和渗透率、地下水流速对DNAPLs运移和分布的影响。研究表明,地下水流速的增大显著促进了DNAPLs的水平和垂向运移;相同流速情况下,非均质层（低渗透性夹层）饱和渗透率的减小使得DNAPLs污染羽形态及空间路径出现了明显蓄积和绕流。模拟结果可为DNAPLs污染场地识别与修复提供了理论基础与技术支持,便于进一步研究其在地下饱和非均质介质中的运移。

英文摘要：

The migration behavior and distribution of Dense Non-aqueous Phase Liquid（ DNAPL） in subsurface porous media is influenced by lots of factors including physical and chemical properties of DNAPL,leakage rate,groundwater flow velocity,and geological heterogeneity. The impact of permeability of layers and flow velocity on migration and distribution of DNAPLs is studied by simulating DNAPLs leakage with T2 VOC using Parker model of three phase capillary pressure function and van Genuchten model of two phase capillary pressure function,respectively. The results show that enhanced flow velocity promotes both the lateral and vertical migration of DNAPLs. In the cases of fixed flow velocity,low permeability of heterogeneous layers leads to an increased spatial variability of distribution morphology of DNAPL plume and percolation paths. Simulations provide theories foundation and technical support for site identification and repair of DNAPLs,and for further studies on migration in subsurface heterogeneous media.