Numerical study of solidification of a drop with a growth angle difference

Abstract

This study presents the direct numerical results of a drop solidifying on a plate, in which the difference between the growth angles is considered. The drop is two-dimensional with the presence of the left and right triple points, and the method used is a front-tracking technique. The growth angles at the right (ϕgr1) and left (ϕgr2) triple points are not equal, i.e. Δϕgr = ϕgr1–ϕgr2 ≠ 0°. Unlike the identical growth angles, the growth angle difference results in an asymmetric drop after complete solidification. In the presence of the solid-to-liquid density ratio ρsl < 1.0 (i.e. volume expansion), the tip of the solidified drop shifts more to the right as Δϕgr increases in the range of 0°–12°. In addition, the angle at the solidified drop top (i.e. tip angle) increases with Δϕgr. We also pay attention to the effects of some other parameters (such as the wetting angle ϕ0, the growth angle ϕgr1 and ρsl) on the solidification process with the growth angle difference. The results reveal that the growth angle varied in the range of 6°–24° has a minor effect on the movement of the tip to the right while the tip shift increases with an increase in ϕ0 in the range of 60°–130° or with a decrease in ρsl in the range of 0.8–1.1. The tip angle increases with an increase in ρsl or with a decrease in ϕgr1 or ϕ0. We also investigate the solidification process under the influence of the Bond number.