Simulation of Particles Dissolution Process in Shear Field using Combined Concentration Lattice Boltzmann–Smoothed Profile Methods

In the present study, the combination of concentration lattice Boltzmann method with a smoothed profile method was used to simulate the dissolution of solid circular particles between parallel plates that are moving in opposite directions. The hydrodynamic simulation was performed based on the single relaxation time lattice Boltzmann method and the convection-diffusion equation was used to determine the concentration of the solute in the liquid phase. Additionally, the smoothed profile method was used to calculate the no-slip boundary condition at the liquid-solid interface and concentration forces. To evaluate the accuracy of the proposed model, the simulation results were compared with the empirical data in the literature. The difference between the simulation results and the empirical data for the Sherwood number at different Peclet numbers was less than 2%. The results show that the smallest dissolution time in systems with different volume fractions is in a system with the least volume fraction. As the volume fraction increases, the solid-liquid mass transfer driving force is decreased in the system. The simulation results showed that by increasing the Reynolds number from 0.05 to 0.38, the time required to reach the normalized volume fraction to 0.05 of its initial value reduced from 0.36 s to 0.17 s. Also, by increasing the Peclet number from 5.5 to 115, the Sherwood number increased from 1.74 to 4.06. In addition, the increase in the Schmidt number in the system leads to a slower dissolution time. Finally, the polydispersity in the system was studied.