Abstract
When a solute A dissolves into a host fluid containing a reactant B, an A + B → C reaction can influence the convection developing because of unstable density gradients in the gravity field. When A increases density and all three chemical species A, B and C diffuse at the same rate, the reactive case can lead to two different types of density profiles, i.e., a monotonically decreasing one from the interface to the bulk and a non-monotonic profile with a minimum. We study numerically here the nonlinear reactive convective dissolution dynamics in the more general case where the three solutes can diffuse at different rates. We show that differential diffusion can add new dynamic effects like the simultaneous presence of two different convection zones in the host phase when a non-monotonic profile with both a minimum and a maximum develops. Double diffusive instabilities can moreover affect the morphology of the convective fingers. Analysis of the mixing zone, the reaction rate, the total amount of stored A and the dissolution flux further shows that varying the diffusion coefficients of the various species has a quantitative effect on convection.
Highlights
Studies on convective flows that can develop when a given phase A dissolves into a host fluid have recently regained interest due to their relevance for CO2 sequestration [1,2]
It is of interest to quantify how reactivity in the host layer can affect the nonlinear dynamics of this convective dissolution and modify the amount of CO2 that can be dissolved per unit of time
We have theoretically analyzed the influence of differential diffusion on the properties of nonlinear dynamics in reactive convective dissolution when a solute A dissolves into a host phase containing a solute B and an A + B → C reaction takes place
Summary
Studies on convective flows that can develop when a given phase A dissolves into a host fluid have recently regained interest due to their relevance for CO2 sequestration [1,2]. Knowing the type of density profile helps predict potential scenarios for the development of the instability, little is known on the nonlinear convective dynamics that can develop when the relative values of the diffusion coefficients are changed In this context, we analyze numerically the impact of differential diffusion effects on the nonlinear dynamics of reactive convective dissolution developing when a solute A increasing density dissolves into a host phase containing a solute B and reacts according to an A + B → C scheme. We show how those variations affect the development of buoyancy-driven fingering, as well as the mixing zone, the global reaction rate, the total amount of stored A and the dissolution flux
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
