微孔中反应流体黏性指进混合过程的数值研究

In this paper, the reactive mixing process with viscous fingering of two miscible solutions in micro-pores is studied at pore scale based on the LBM modules of the National Numerical Wind Tunnel software. Considering the chemical reaction between the two solutions and the precipitation of reaction product, we focuse on the effects of the chemical reaction rate, the nucleation rate and the aggregation rate of the solid product on the viscosity fingering. It is found that the chemical reaction obviously changes the concentration distribution of the interface of the viscous finger, and the change of the components at the finger interface increases with the chemical reaction rate. On the other hand, when the reaction rate increases above a certain value, the concentration remains nearly constant due to the limitation of diffusion process. In addition, the amount of reaction product is positively correlated with the reaction rate and negatively correlated with the nucleation rate and aggregation rate, and the concentration of solid component is positively correlated with the nucleation rate and aggregation rate positively. Finally, it is found that the mixing length is mainly related to the chemical reaction rate, nearly independent on the nucleation and aggregation rates.