中文摘要：

针对多孔介质中水、气和非水相流体的多相流动特点，建立了描述非水相流体污染物迁移问题的数学模型。采用离心模型试验和数值分析的方法模拟了土壤非饱和区中的多相流动过程，得到了污染物的时空分布特征和污染范围。模型试验和数值分析结果表明，轻非水相流体在地表泄漏后，会在重力作用下进入非饱和土体并向下迁移，部分滞留于土体孔隙中；到达地下水位时会浮在水面上并且继续侧向运移；水文地质条件对非饱和土中多相流动特征有重要的影响。

英文摘要：

Based on the theory ofmultiphase flow in porous media, analytical model for NAPL transport in soils is proposed and developed in this paper. Firstly, centrifuge testing and numerical simulation are employed to model the multiphase flow through unsaturated soils, and hence the tempo-spatial distribution and contamination extent are obtained. Then the migration behavior of NAPL in unsaturated soils is analyzed. It is shown that 1） after ground spill, LNAPL enters into unsaturated soils and moves downwards by gravity force, with some retained in pore-S of soil mass; 2） when reaching underground water table, LNAPL floats on it and continues to migrate; 3） hydro-geological condition has significant effect on multiphase flow.