![]() The diffusive theoretical profile describes perfectly the numerical profile at t = 0.2 s, but the two profiles differ at later times, in the quasistationary regime. From bottom to top, t = 0.2, 10, and 50 s. These numerical profiles are compared to the analytical diffusive solutions ( 17) (dashed green lines). The blue area shows the fluctuation (standard deviation) around the mean profile. Blue lines show the result of the numerical simulation for t = 0.2 s and t > 10 s the latter is an average in the quasistationary regime. Even for minerals with a quite low saturation concentration, the erosion rate would increase as the dissolution would be controlled by the hydrodynamics. ![]() Our results suggest that solutal convection could occur in more natural situations than expected. We predict the typical dissolution rate in the presence of solutal convection. We apply the scaling laws previously established to the case of real dissolving minerals. We find a constant value of the Rayleigh number during the quasistationary regime, showing that the structure of the boundary layer is well controlled by the solutal convection. Our simulations confirm this scenario by validating the scaling laws for both onset and the quasistationary regime. Assuming that the destabilization of the boundary layer occurs at a specific value of the solutal Rayleigh number, we derive scaling laws for both fast and slow dissolution kinetics. This last regime is quasistationary: The structure of the boundary layer and the erosion rate fluctuate around constant values. Finally, the destabilization is such that we observe the emission of intermittent plumes. After a finite onset time, the thickness and the density reach critical values, which starts the destabilization of the boundary layer. At a short timescale, a concentrated boundary layer grows by diffusion at the interface. We simulate numerically the hydrodynamics and the solute transport in a two-dimensional geometry, corresponding to the case where a soluble body is suddenly immersed in a quiescent solvent. Here we perform a study of the physics of solutal convection induced by dissolution. Even in the absence of an external flow, dissolution itself can induce a convective flow due to the action of gravity. The dissolution of minerals into water becomes significant in geomorphology when the erosion rate is controlled by the hydrodynamic transport of the solute.
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