The Relative Contribution of Solutal Marangoni Convection to Thermal Marangoni Flow Instabilities in a Liquid Bridge of Smaller Aspect Ratios under Zero Gravity
The Relative Contribution of Solutal Marangoni Convection to Thermal Marangoni Flow Instabilities in a Liquid Bridge of Smaller Aspect Ratios under Zero Gravity
复制标题
DOI：
10.3390/cryst11020116
复制
发表时间：
2021-01
期刊：
影响因子：
--
通讯作者：
Radeesha Laknath Agampodi Mendis;A. Sekimoto;Y. Okano;H. Minakuchi;S. Dost
中科院分区：
文献类型：
--
作者：
Radeesha Laknath Agampodi Mendis;A. Sekimoto;Y. Okano;H. Minakuchi;S. Dost
采用三维数值模拟方法研究了失重条件下不同长径比As的Si-Ge液桥中溶质Marangoni对流对热Marangoni对流存在时流动不稳定性的影响。我们考虑一个半区模型之间的冷（顶部平面）和热（底部平面）磁盘的液体桥。硅浓度最高的位置在液桥的顶部。纵横比（As）显著影响临界Marangoni数：临界溶质Marangoni数（在小的热Marangoni数（MaTA ≤ 1800）下）与临界热Marangoni数（在小的溶质Marangoni数（400 μ MaCA ≤ 800）下）具有相同的As依赖性，即，它随As的增加而减少。行波模式的方位波数随着As的减小而增加，即，当As=0.25时，出现较大的方位波数（m= 6，7，11，12和13），当As大于1时，仅出现m=2。利用动力学模式分解（DMD）方法提取了水波振荡模式的时空结构。本研究提出了一个合适的参数范围的静态稳定流适合晶体生长较小的液桥的纵横比。
The effect of solutal Marangoni convection on flow instabilities in the presence of thermal Marangoni convection in a Si-Ge liquid bridge with different aspect ratios As has been investigated by three-dimensional (3D) numerical simulations under zero gravity. We consider a half-zone model of a liquid bridge between a cold (top plane) and a hot (bottom plane) disks. The highest Si concentration is on the top of the liquid bridge. The aspect ratio (As) drastically affects the critical Marangoni numbers: the critical solutal Marangoni number (under small thermal Marangoni numbers (MaTAs≲1800)) has the same dependence on As as the critical thermal Marangoni number (under small solutal Marangoni numbers (400≲MaCAs≲800)), i.e., it decreases with increasing As. The azimuthal wavenumber of the traveling wave mode increases as decreasing As, i.e., larger azimuthal wavenumbers (m=6,7,11,12, and 13) appear for As=0.25, and only m=2 appears when As is one and larger. The oscillatory modes of the hydro waves have been extracted as the spatiotemporal structures by using dynamic mode decomposition (DMD). The present study suggests a proper parameter region of quiescent steady flow suitable for crystal growth for smaller aspect ratios of the liquid bridge.