本文采用格子Boltzmann方法模拟了多孔介质内的溶解和沉淀现象，并分析了雷诺数、施密特数、达姆科勒数对多孔介质孔隙结构及浓度分布的影响。结果表明：对于多孔介质内的溶解(沉淀)过程，当雷诺数越大时，孔隙率越大(小)，平均浓度值越小(大)；当达姆科勒数或施密特数较小时，溶解和沉淀过程均受反应控制，此时反应在多孔介质的固体表面较为均匀的发生；当达姆科勒数或施密特数较大时，溶解和沉淀过程均受扩散控制，此时反应主要发生在上游及大孔隙区域。%In this paper, we simulate numerically the dissolution and precipitation in porous media by using the lattice Boltzmann method (LBM). The fluid flow in porous media is simulated by using a multiple-relaxation-time (MRT) LBM, while a D2Q9 lattice BGK model is used for reactive solute transport. First, the code of LBM is tested by simulating the diffusion and reaction at a boundary in an open rectangular domain, and comparing the results with the analytic solution. Then, the effects of the Reynolds number (Re), the Schmidt number (Sc) and the Damkohler number (Da) on the variations of the geometry of the porous media and the concentration field are carefully studied. It can be found that for the dissolution (precipitation), as Re is increased, the porosity of the porous media will be increased (decreased), and the average concentration will be decreased (increased). Besides, at low Damkohler numbers or Schmidt numbers, the dissolution and precipitation will be reaction-controlled and are highly uniform. However, as Da or Sc is high, the dissolution and precipitation will be diffution-controlled, and mainly occur in the upstream and large pore space.
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