Department of Applied Physics, Tokyo University of Science, Tokyo 125-8585, Japan.
Department of Education, Aichi University of Education, Aichi 448-8542, Japan.
Phys Rev E. 2017 May;95(5-1):052220. doi: 10.1103/PhysRevE.95.052220. Epub 2017 May 31.
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.
受限化学花园的图案是通过注入液体的速度来控制的，并且讨论了其机制。构建了一个受限化学花园系统，其中将氯化钴水溶液注入充满硅酸钠溶液的单元中。这两种溶液的反应导致沉淀的形成。为了排除 Saffman-Taylor 不稳定性的可能性，将制备的水溶液的粘度设置为相似。注入前沿显示出三种不同的图案：藻类、贝壳和细丝，这取决于注入速度。测量了注入压力和注入流体的时空模式，当出现细丝图案时，观察到注入压力显著增加，这表明沉淀和基底之间存在薄的润滑层。进一步对细丝图案进行了定量分析，确定了活性细丝的数量与注入速度成正比。构建了一个数学模型，该模型同时考虑了来自薄润滑层的粘性效应和拉普拉斯压力。该模型成功地再现了特征细丝动力学。
