Demange Gilles, Patte Renaud, Zapolsky Helena
GPM, CNRS-UMR 6634, University of Rouen Normandy, Saint Étienne Du Rouvray 76801, France.
Philos Trans A Math Phys Eng Sci. 2022 Feb 21;380(2217):20200304. doi: 10.1098/rsta.2020.0304. Epub 2022 Jan 3.
The present work is devoted to the phenomenon of induced side branching stemming from the disruption of free dendrite growth. We postulate that the secondary branching instability can be triggered by the departure of the morphology of the dendrite from its steady state shape. Thence, the instability results from the thermodynamic trade-off between non monotonic variations of interface temperature, surface energy, kinetic anisotropy and interface velocity within the Gibbs-Thomson equation. For the purposes of illustration, the toy model of capillary anisotropy modulation is prospected both analytically and numerically by means of phase-field simulations. It is evidenced that side branching can befall both smooth and faceted dendrites, at a normal angle from the front tip which is specific to the nature of the capillary anisotropy shift applied. This article is part of the theme issue 'Transport phenomena in complex systems (part 2)'.
本研究致力于由自由枝晶生长中断引发的诱导侧枝现象。我们假设二次分支不稳定性可由枝晶形态偏离其稳态形状触发。因此，这种不稳定性源于吉布斯 - 汤姆逊方程中界面温度、表面能、动力学各向异性和界面速度的非单调变化之间的热力学权衡。为了说明这一点，通过相场模拟对毛细管各向异性调制的简化模型进行了分析和数值研究。结果表明，侧枝可以出现在光滑和有小面的枝晶上，其与前端的法线角度特定于所应用的毛细管各向异性变化的性质。本文是主题为‘复杂系统中的输运现象（第2部分）’的一部分。
