Flow and solute transport in dissolutive wetting

Liquid spreading on a soluble substrate is known as dissolutive wetting, a common phenomenon in the medical and industrial fields. However, the dynamic process of dissolutive wetting is not fully understood due to the complex transport of mass and momentum. In this article, we present a hydrodynamic model that accounts for both Marangoni and buoyancy effects to analyze interface shape, flow, and solute transport in dissolutive wetting. Based on our theoretical analysis and experiments, we propose two dimensionless numbers, Ya and Pe′, to plot a phase diagram of dissolutive wetting. We investigate the evolution of the flow field, concentration field, and solid–liquid interface shape for different types of dissolutive wetting. Furthermore, we discovered a new type of dissolutive wetting resulting from the competition between Marangoni convection and buoyancy, using both experimental and theoretical approaches. Our study provides significant insight into dissolutive wetting, which may has applications in joining processes of materials, material synthesis, structural fabrication, and so on.