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| COUPLED FLUID FLOW AND CHEMICAL DISSOLUTION MODEL BASED ON SURFACE REACTION AND MASS TRANSFER CONTROL IN A ROUGH FRACTURE |
| HUO Jixiang，SONG Hanzhou，DU Jingnong，GUAN Qingchen |
| (College of Earth Sciences and Engineering，Hohai University，Nanjing，Jiangsu 210098，China) |
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Abstract The variations of flow，chemical fields and aperture in a fracture could be described by the model of coupled fluid flow and chemical dissolution，which were affected by the dissolution rate and the initial distribution of aperture. Two factors，the surface reaction and the mass transfer，were considered to control the dissolution process. A rough fracture was generated numerically with the fractal theory and a model of coupled fluid flow and chemical dissolution was thus established and numerically solved. The results showed that the distribution of aperture，flow velocity and concentration of appeared as inhomogeneous wormholes. The flow through the fracture increased during the whole period of simulation，while the growth rate of flow increased sharply at a certain moment，called the breakthrough time. The factor controlling the chemical reaction varied during the dissolution，was the surface reaction initially and then was turned to the mass transfer on the upstream and extended to downstream gradually.
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2015, Vol. 34 
