In this study, the solidification process of a compound droplet is numerically simulated by an axisymmetric front-tracking/finite difference technique. The compound droplet placed on a cold flat surface in a gas environment consists of an inner gas core surrounded by a concentric shell phase-change liquid that forms an outer droplet. The initial droplet shape assumed as a spherical cap is therefore determined by two wetting angles known as the inner wetting angle (ϕ_0i for the inner core) and the outer wetting angle (ϕ_0o for the outer droplet). During the solidification process, there is the presence of two three-junction points where a prescribed growth angle ε is specified. We analyze the solidification process undergoing the influence of the geometrical aspects of the compound droplet including the growth angle and the wetting angles. It is found that the outer wetting angle ϕ_0o and the growth angle have a strong influence on the solidified droplet that the droplet height increases with an increase in ϕ_0o or ε while the height increment decreases with an increase in ϕ_0o or with a decrease in ε. On the contrary, changing the shape of the inner core, in terms of ϕ_0i, does not affect the outer shape after complete solidification. The effects of these parameters on the solidification time are also considered.

在这项研究中，复合液滴的凝固过程通过轴对称前跟踪/有限差分技术进行数值模拟。放置在气体环境中冷平面上的复合液滴由内部气核组成，内部气核被同心壳相变液体包围，形成外部液滴。因此，假设为球冠的初始液滴形状由两个润湿角决定，称为内润湿角（对于内核为ϕ _{0 i}）和外润湿角（对于外液滴为ϕ _{0 o}）。在凝固过程中，存在两个三结点，其中规定的生长角为ε被指定。我们分析了受复合液滴几何方面影响的凝固过程，包括生长角和润湿角。据发现外润湿角φ _{0 Ò}和生长角度对固化的液滴具有强烈的影响，与增加了微滴高度的增加φ _{0 ö}或ε而高度增量的增加而减小在φ _{0 Ò}或随着ε的减小。相反，改变内核的形状，根据ϕ _{0 i}, 完全凝固后不影响外形。还考虑了这些参数对凝固时间的影响。