Thermal and Fluid Flow of Immiscible Two-Layer Liquids in Vertical Cylindrical Container. Application to Solid Spherical Shell Generator in Liquid-Liquid-Gas Systems.

Abstract

Solid spherical shells of mm-order diameter can be applied to lightweight structural materials, buoyant catalytic agents, high-performance solid fuels, and artificial organs. The sequential spherical shell generator in liquid-liquid-gas systems comprised of a cylindrical container containing two immiscible liquids and a gas injection nozzle at the center of the bottom. By controlling the gas flow and the temperature field of the two-layer liquids, liquid spherical shells were formed at the interface between the two immiscible liquids and were solidified during the upward motion. For the stable production, it is necessary to correctly estimate the thermal fluid flow and to control the temperature field in the two-layer liquids with high accuracy. To develop the sequential solid spherical shell generator, natural convection heat transfer in the irnmiscible two-layer liquids in the cylindrical container was studied. By solving the incompressible Navier-Stokes equations and the energy equations for the upper and lower liquids, the flow patterns and thermal field of the two-layer liquids were quantitatively investigated. The suitable conditions for the sequential production of solid spherical shells were explored.