Low-Prandtl Number Buoyancy and Surface Tension Induced Convection with/without Solidification and Mushy Zone

提出了一种新的X射线流动显示技术，该技术是由美国国家科学基金会的研究设备资助发起的，用于研究浮力和表面张力诱导的对流及其与材料加工(包括晶体生长和铸造)相关的模型系统中的相变的相互作用。这项技术基于冶金相容的中性浮力示踪粒子的使用，与熔体相比，这些粒子的辐射不透明程度更高。拟议的工作将包括进一步发展射线示踪技术以及对流引导的凝固过程的研究，包括糊状区的形成。

A novel radiographic flow visualization technique, whose development was initiated under a NSF research equipment grant, is proposed to study the buoyancy and surface tension induced convection and their interaction with phase change in model systems relevant to materials processing, including crystal growth and casting. The technique is based on the use of metallurgically compatible, neutrally buoyant tracer particles which are more radio-opaque compared to the melt. The proposed work will include further development of the radiographic tracer technique as well as studies on the convection-mediated solidification processes, including the formation of mushy zone.