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本文应用高温实时观察法显示了二种对流状态：扩散一平流状态和扩散-重力对流状态，并测出它们的特征扩散长度为0.01～0.1cm．通过晶体旋转生长，计算了质量、热量和动量变换区厚度，数值分别为7．5×10-3Cm；86×10－2cm和44×10－1本文还应用高温实时观察法进一步研究了上述二种不同对流状态下的KNbO3（001）晶面的生长动力学，实验结果指出：（1）在同一过冷度条件下，扩散一平流状态下的生长速度大于扩散一重力对流状态下的生长速度；（2）在过冷度小于20℃时，二种对流状态下的KNbO3（001）晶面生长机理都服从二维成核生长，但台阶自由能ε和二维晶核的形成热力学势能△G等生长参数不一致，从而表明这些参数是实验研究熔体对流对晶体生长界面动力学的重要依据，并指出熔体对流效应增强了界面的奇异性．
In this paper, two kinds of convection states, diffuse-advection state and diffusion-gravity convection state, were observed by high temperature real-time observation. Their characteristic diffusion length was measured to be 0.01-0.1 cm. Through the crystal rotation growth, the thickness of mass, heat and momentum transformation area are calculated, the values are 7.5 × 10-3Cm, 86 × 10-2cm and 44 × 10-1 respectively. In this paper, The results show that: (1) Under the same subcooling condition, the growth rate in the diffusion-advection state is larger than the growth rate in the diffusion-gravity convection state ; (2) At the subcooling degree of less than 20 ℃, the growth mechanism of KNbO3 (001) plane under both convection states obeys two-dimensional nucleation and growth, but the step free energy ε and the formation of two-dimensional nuclei thermodynamic potential △ G and other growth parameters are inconsistent, indicating that these parameters are experimental study of melt convection on the crystal growth interface kinetics important basis and pointed out that the melt convection effect enhances the interface of the singularity.