强迫对流对树的作用:恒定和变化流量场之间的比较
Lang Qin1, Ang Zhang1, Jinglian Du2
1National Engineering Research Center for Magnesium Alloys, National Key Laboratory of Advanced Casting Technologies, College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
Materials (Basel, Switzerland)
|December 23, 2023
概括
交流显著影响 dendrite 的生长. 这项研究揭示了不同的流量模式,包括恒定和变化的流量,如何影响树石不对称性,为材料加工控制提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 流体动力学 流体动力学
- 计算物理 计算物理
背景情况:
- 交流在 dendite 的形成中起着至关重要的作用.
- 以前的研究经常将融流简化为恒定水平流,限制了理解.
- 卷积和树形态之间的复杂相互作用需要进一步研究.
研究的目的:
- 为了研究各种对流行为对 dendrite 增长的影响.
- 在不同的流量条件下量化树生长的不对称性.
- 开发基于流量参数的树异对称性的预测模型.
主要方法:
- 用相场格子-博尔兹曼方案进行模拟.
- 强加了四种不同的对流模式:均分布,线性分布,正弦波和正方波.
- 使用上游和下游初级臂的长度比率量化树石不对称.
主要成果:
- 不断的对流导致了状石的不对称性增加.
- 改变对流 (正弦波和正方波) 会导致不对称的非单调变化.
- 一个数学关系被用来描述树石不对称性对速度,低冷却和流动频率的依赖.
结论:
- 交流显著影响 dendrite 形态,而不仅仅是简单的水平流.
- 了解各种对流模式是预测和控制树突形成的关键.
- 这些发现为优化在复杂流量条件下的造和加工提供了指导.
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