空间高温氧化物晶体生长过程中流体效应的数字模拟研究  

Numerical Simulation Study of High Temperature Oxide Crystal Growth in Space

作　　者：刘照华[1] 金蔚青[1] 潘志雷[1] 梁歆桉[1] 陈刚毅[1] 

机构地区：[1]中国科学院上海硅酸盐研究所,上海200050

出　　处：《人工晶体学报》2002年第4期345-349,共5页Journal of Synthetic Crystals

基　　金：国家科学技术委员会攀登项目 (95 预 3 4);国家自然科学基金 (5 983 2 0 80 )资助项目

摘　　要：数字模拟方法可以模拟实际晶体生长过程 ,了解晶体生长参数的变化对晶体生长的影响。本文利用数字模拟的方法 ,在本实验室建立的空间二维实时观察装置中 ,对高温Li2 B4O7熔液中生长KNbO3 晶体的流体效应及温场进行了数字模拟研究 ,结果表明 ,在地面生长 ,熔液内部存在复杂的双涡流动模式 ,重力对熔液中的速度场和温场的分布产生强烈的作用 ,而在空间 ,当重力水平达到一定程度时 ,可以使熔液中的流动模式简单化 ,从而降低流动效应对传热、传质造成的不稳定性和不均匀性 ,有利于提高晶体生长的质量。同时通过对空间搭载实验与地面实验结果进行对比分析 ,与数字模拟分析的结果一致 ,随着重力水平的下降 ,熔液中的速度场 ,温场分布朝着稳态生长的方向发展 。The numerical simulation is a rather good way to learn the influence of parameter variables on crystal growth. The fluid flow effect and temperature field in high temperature oxide melt solution crystal growth were simulated numerically in the two dimensional space in situ observation facility.The results indicated that the complicated couple vortex mode in melt solution was found under ground crystal growth and the gravitation had an important influence on the distribution of temperature field and velocity field of melt solution. But in space,when the gravity level arrived to some extent,the simplest flow mode appeared and the fluid flow effect had little influence on the unstability resulted from the heat transport and mass transport in melt solution crystal growth.Meantime,the analysis on the comparison between the space and the ground experiment agreed with the numerical simulation. The temperature field and velocity field developed to the steady crystal growth with decreasing the gravity level and the surface tension convection was the main factor which formed the complete cellulation.

关 键 词：空间高温氧化物 晶体生长过程 流体效应 数字模拟 研究 微重力 速度场 温度场 

分 类 号：O781[理学—晶体学]