Chemoconvection of miscible solutions in an inclined layer

This paper presents an experimental and numerical investigation of the chemoconvective flow two miscible reacting solutions that generate a plain layer oriented at some angle to gravity field. In experiments, aqueous nitric acid sodium hydroxide were used. The system evolves from initial state, in which each homogeneous solution occupies half layer, contact surface between layers is flat. When come into with other, acid-base neutralization reaction occurs, forming salt water. configuration chosen so lower density rests on top denser base. excludes development Rayleigh–Taylor instability. experiments performed for such concentrations reagents wave regime realized system. comprises jump rapidly advancing direction separating immobile alkali mixture, convective motion feeds frontal fresh acid. visualization was using Fizeau interferometer. study complete three-dimensional problem carried out ANSYS CFX hydrodynamic simulation program. We studied evolution gradual increase inclination 0° 70°. found leads significant change structure intensity motion. Already small angles (up 30°), becomes three-dimensional, makes Hele-Shaw approximation inapplicable this case. show there spontaneous stratification concentration fields cocurrent flow. With inclination, velocity decreases, chemoconvection less intense acquires certain vortex structure. At larger (from 50° 70°), front strongly deformed or breaks up. demonstrate up-and-down fluid develops above jump. eventually loses its stability respect vertical rolls solutal Rayleigh convection. There good agreement measurements results 3D problem.