论文标题
部分可观测时空混沌系统的无模型预测
The influence of anisotropy on the evolution of interfacial morphologies in directional solidification: A phase-field study
论文作者
论文摘要
通过调节界面能，曲率和速度，各向异性在界面过程和传输过程之间的相互作用中起着重要作用，从而确定凝固结构。在本文中，研究了各向异性对方向固化中界面形态进化的影响。为了表示不同的界面各向异性，进行了具有不同首选晶体学取向的固化过程。然后系统地讨论各向异性对形态进化的影响。在平面生长阶段，界面各向异性在运输过程和形态进化中没有差异。在平面不稳定性的开始时，各向异性通过调节界面刚度来决定详细的演变。在平面细胞转变阶段，随着各向异性的影响，界面曲率从θ0= 0°降低至θ0= 40°。因此，界面前的溶质浓度从θ0= 0°增加到θ0= 40°，而界面的瞬时速度从θ0= 0°降至θ0= 40°。在准态状态阶段，各向异性决定了主要树突的生长方向和尖端速度，以及侧枝的开始。
By adjusting the interface energy, curvature, and velocity, the anisotropy plays an important role in the interaction between interfacial processes and transport processes, determining the solidification structures. In this paper, through the quantitative phase-field model, the influence of anisotropy on the evolution of interfacial morphologies in directional solidification is investigated. To represent different interfacial anisotropies, the solidification processes with different preferred crystallographic orientations are performed. Then the effect of anisotropy on morphological evolution is discussed systematically. At the planar growth stage, the interfacial anisotropy makes no difference in the transport processes and morphological evolution. At the onset time of planar instability, the anisotropy determines the detailed evolution by adjusting the interface stiffness. At the planar-cellular-transition stage, with the influence of anisotropy, the interfacial curvature decreases from θ0=0° to θ0=40°. Hence, the solute concentration ahead of the interface increases from θ0=0° to θ0=40°, while the instantaneous velocity of the interface decreases from θ0=0° to θ0=40°. At the quasi-steady-state stage, the anisotropy determines the growth direction and tip velocity of the primary dendrite, as well as the onset of sidebranches.
