title: [Fractal characteristics of capillary finger flow for NAPLs infiltrated in porous media].
abstract: Non-aqueous phase liquids (NAPLs) like petroleum hydrocarbons and chlorinated solvents have resulted in contamination of soils and ground water, which aroused widespread concern. It's quite important to delineate pollution area for remediation according to different soil types with pollutants properties in consideration. In this paper, a two-dimension visual sand box apparatus was constructed, with four typical NAPLs selected for infiltration experiments conducted in initially dry porous media. The main driving force was identified and fingering patterns were compared. The fractal dimension was used to give quantitative description. The present work indicates that the main driving force was capillary forces and the mechanism was the capillary fingering. The fingers varied from skeletal patterns to fleshy patterns and the infiltration area increased when the capillary number and the bond number decreased for NAPLs with the same level of viscosity. The high viscous force resulted in larger finger width and infiltration area. The same change between fluids happened in finer media. Fractal dimensions were positively correlated with the finger width and infiltration area, which is helpful in the pollution area characterization.
authors.affiliation: Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, Beijing Normal University, Beijing 100875, China. lihy@craes.org.cn
authors.forename: Hui-Ying
authors.initials: HY
authors.lastname: Li
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Du
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Ji-Dun
authors.initials: JD
authors.lastname: Fang
authors.affiliation: Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education, Beijing Normal University, Beijing 100875, China.
authors.forename: Fa-Sheng
authors.initials: FS
authors.lastname: Li
mesh_terms: D004787:Environmental Pollution / Q000032:analysis*; D017709:Fractals; D006838:Hydrocarbons / Q000032:analysis; D010578:Petroleum / Q000032:analysis; D016062:Porosity; D012822:Silicon Dioxide; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis
chemical_list: D006838:Hydrocarbons; D010578:Petroleum; D012987:Soil; D012989:Soil Pollutants; D012822:Silicon Dioxide