Self-organization of TiO2 microparticles on the surface of a thin liquid layer due to local heating and the formation of convective cells

• Published in: Journal of molecular liquids Vol. 324; p. 114685
• Main Authors: Egorov, R.I., Misyura, S.Y., Morozov, V.S., Zaitsev, A.S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2021
• Subjects: Benard-Marangoni convection; Laser heating; Liquid interface; Microparticles; Self-assembly; Self-assembly; Laser heating; Benard-Marangoni convection; Microparticles; Liquid interface
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2020.114685

The aggregation of TiO2 microparticles followed by self-organization of a cluster of agglomerates at convective cells formation in a thin layer of water is studied experimentally. Complex behavior of the cluster is considered at a strong system deviation from equilibrium as a result of local heating. A periodic character of the behavior of a cluster of particles has been detected. Particle sizes and the number of cells change cyclically over time. Hexagonal convective cells have a very small size of about 50–100 μm (5–10 times less than the layer height). Data on the cluster occurrence and dissociation over time is provided. It is shown that when the particle diameter and the diameter of coagulated particles reach the maximum (the maximum diameter of the cluster corresponds to 100–130 μm, and the maximum diameter of the aggregate is 20–30 μm), the convective cells lose stability and the cluster partially disintegrates. Self-organization control using local heating can be effectively applied to create new materials, as well as in biology and medicine. •Self-organization convective cells and micro-particles cluster formation is studied.•Perturbations at the micro level control the average flow at the macro level.•Stochastic nature of the averaged flow is associated with micro scales.•Integral convection scale corresponds to 2.5 mm.