Centrifugal convection in a two-layer system of reacting miscible fluids

Abstract

The authors study the effect of uniform rotation on the system of two reacting miscible liquids placed in a cylindrical Hele-Shaw cell. The cell performs a rotation with a constant velocity around the axis of symmetry resulting in a radially directed inertial field. The initial configuration of the system is statically stable and consists of two concentric layers of aqueous solutions of acid and base, which are spatially separated. When liquids are brought into contact, a neutralization reaction begins, which is accompanied by the release of salt. In this work, we obtain a system of governing equations and present the results of numerical simulation. We found that reaction-diffusion processes lead to the formation of a non-monotonic density profile with a potential well. If the rotation rate gradually increases, then a cellular convection pattern can develop in the potential well. We found that with further growth of the control parameter, the periodicity of the pattern is violated due to the influence of another convective instability, which independently develops in the domain close to the axis of rotation. The action of the inertial field results in the ejection of some convective vortices from the potential well.