The 10th Asian Symposium on Computational Heat Transfer and Fluid Flow ( ASCHT2025)

In this paper, we construct a unified diffuse-interface model for reactive transport involving solid dissolution and precipitation. This model integrates the diffuse-domain method for fluid flow and solute transport, thereby treating the fluid and solid regions as a whole computational domain. This formulation inherently circumvents handling of complex nonlinear velocity and reaction boundary conditions on  fluid-solid interfaces, a significant challenge in classical Navier-Stokes and solute transport equations with sharp interfaces. Furthermore,  we propose a diffuse-interface model for the solid volume evolution and rigorously derive its sharp-interface limits, demonstrating that the interface velocity is driven solely by chemical reaction as the fluid-solid interface thickness approaches zero. To efficiently solve the coupled diffuse-interface system, we employ the lattice Boltzmann (LB) method. The inherent particle-based nature of LB facilitates direct multi-field coupling by LB evolution equations. Validation through two-dimensional and three-dimensional numerical cases verifies the accuracy and efficiency of the proposed method. Consequently, the proposed numerical scheme offers low computational cost and high parallel efficiency, making it well-suited for large-scale simulation of reactive transport with solid dissolution/precipitation in complex pore structures. 

Phase field,lattice Boltzmann method,reactive transport,dissolution and precipitation