Study on Flow with Phase Transtition in Sequential Production Technique of High Quality Solid Spherical Shells

可应用于各个技术领域的毫米级高质量实心球壳的连续生产是目前研究的课题。利用液-液-气系统中液体球壳和固体球壳序贯生产装置，对固体球壳的经济生产进行了系统的实验和理论研究，以改进生产装置，提供基础的设计数据。此外，本生产装置还成功地生产了金属球壳。测量了宽流量条件下的管径和生产频率。本研究的主要方向如下：(1)设计了一种新型的液-液-气系统固体球壳生产装置，并认识到固体球壳的生产频率比以前使用的装置大。(2)数值分析了非混相两液层内液体物理性质对两液层自然对流的影响。因此，当下层液体的Grashof数较大，上层液体的Grashof数和Prandtl数较小时，上层液体和液-液界面之间的温差变大，这是连续生产固体壳的适宜条件。(3)数值分析了设置防自然对流板对生产装置内温度分布的影响。可以通过设置板来精确控制自然对流。(4)通过对垂直圆柱形容器内两层液体自然对流换热的数值分析，提出了生产固体壳的容器长径比的适宜条件。(5)本装置成功地生产了金属壳，这是以前的装置很难做到的。(6)详细观察了液-液界面金属壳生成的流动机理。(7)测量了各种流动条件下的管径、生产频率、壳体厚度和变形比。提出了壳体直径预测的经验公式。少

The sequential production of mm-sized and high-quality solid spherical shells, which can be applied to various fields of technology, is the subject to the present research. Using the sequential production device of liquid spherical shells and solid spherical shells in liquid-liquid-gas systems, the experimental and theoretical research on the economical production of solid spherical shells is made systematically to improve the production device and to provide the basic design data. Furthermore, the metallic spherical shells are successfully produced by the present production device. The diameter and production frequency for wide flow conditions are measured. The main futures of the present research are as follows : (1) The new production device of solid spherical shells using liquid-liquid-gas systems is designed, and it is recognized that the production frequency of solid shells becomes larger than that using previous device. (2) The effects of physical properties of liquids in the pr … More oduction device on the natural convection in immiscible two liquids layr are analyzed numerically. Consequently, when the Grashof number of lower liquid is large and when the Grashof number and Prandtl number of upper liquid are smaller, the temperature difference between the upper liquid and the liquid-liquid interface becomes large, which is the suitable condition for sequential production of solid shells. (3) The effects of setting the plate for prevention of natural convection on the temperature distribution in the production device are analyzed numerically. It is possible to precisely control the natural convection by setting the plate. (4) By the numerical analysis of natural convection heat transfer in two-layr liquids in vertical cylindrical container, the suitable condition of aspect ratio of container for solid shells production is proposed. (5) The metallic shells are successfully produced by the present device, which is very difficult using the previous device. (6) The flow mechanism of production of metallic shells at the liquid-liquid interface is observed in detail. (7) The diameter, production frequency, shell thickness and deformation ratio are measured for various flow conditions. The empirical equation for prediction of shell's diameter is proposed. Less