Interfacial mass transfer in immiscible reactive two-phase flows are ubiquitous in industrial processes and chemical synthesis. In this work, we first extend the immiscible two-phase flow under sharp-interface to the diffuse domain. Then, we use a flux-forcing function as a source term in the equations of reactant and product to impose the heterogeneous reaction conditions at the interface, and the derivation of the proposed model is completed through the weak form of the convection-diffusion equation. To solve the resulting governing equations, a phase-field lattice Boltzmann (LB) method is developed and validated against benchmark problems. The simulation results show that the proposed model and LB method are in a good agreement with the analytical solutions. Then we investigate a single droplet in lid-driven cavity flow and multiple droplets in rotating cylindrical cavity flow under different driven velocities. These results indicate that the proposed diffuse-interface model can well describe the heterogeneous reaction at the immiscible two-phase interface, and the developed LB method exhibits robustness and computational efficiency, establishing a foundation for industrial applications in multi-phase reactive systems.

Lattice Boltzmann method,immiscible flow,heterogeneous reaction,phase-field method