Pattern of a confined chemical garden controlled by injection speed

Abstract

Pattern of confined chemical garden was controlled by the speed of injected fluid, and their mechanism is discussed. A confined chemical garden system was constructed where an aqueous solution of cobalt chloride was injected into a cell filled with sodium silicate solution. The reaction of these two solutions resulted in the formation of precipitation. The viscosities of the prepared aqueous solutions were set to be similar in order to rule out the possibility of Saffman-Taylor instability. The injection front showed three distinctive patterns: algaes, shells, and filaments, which were dependent on injection speed. The injection pressure and the spatio-temporal pattern of the injected fluid were measured, and a significant increase in the injection pressure was observed when the filament pattern appeared, which indicated the existence of thin lubrication layer between the precipitation and the substrate. The filament pattern was further analyzed quantitatively, and the number of active filaments was determined to be proportional to the injection speed. A mathematical model was constructed that considered both the viscous effect from the thin lubrication layer and the Laplace pressure. This model successfully reproduced the characteristic filament dynamics.

Filament dynamics in planar chemical gardens

“…An increase in the flow rate leads to the formation of a single filament, and a further increase in flow rate will eventually lead to the onset of multiple filaments at once. From that point onwards, higher flow rates will simply affect the number of filaments that are formed 21 . The filaments mentioned here correspond to the F1 structures described by Haudin et al 8 ; these consist of narrow, elongated tubular structures.…”

Chemobrionic structures in tissue engineering: self-assembling calcium phosphate tubes as cellular scaffolds

“…14,15 Alternatively, the controlled injection of a cationic solution into an anionic reservoir (and vice versa), can provide unique insights into growth regimes during self-assembly and offer greater influence over precipitate composition. [16][17][18][19] Injection system set-ups can also be adapted to mimic the chemistry found in the early oceans of Earth in order to help understand the origins of life on our planet. [20][21][22] Surprisingly, there is relatively little work that examines the use of such systems for biotechnological applications.…”

Influence of microscopic precipitate structures on macroscopic pattern formation in reactive flows in a confined geometry

“…Flow conditions have recently been shown to be able to affect the yield of precipitation reactions 1,2 as well as the spatiotemporal distribution of the solid phase produced. [1][2][3][4][5][6][7][8][9] Experiments consisting of injecting a solution of a given reactant of a precipitation reaction into a confined geometry containing a solution of the other reactant have indeed made it possible to show that, depending on the concentrations of the chemicals and the injection flow rate, various precipitation patterns can be obtained. The resulting structures depend not only on the cohesion of the solid phase produced by the reaction but also on possible hydrodynamic instabilities.…”