喷流转晶法KDP晶体生长系统的流动与传质模拟

提出了一种通过锥顶喷流改善KDP锥面过饱和度的晶体生长方法。采用有限体积法和滑移网格技术,对传统转晶法及喷流转晶法的KDP晶体生长过程进行了数值模拟。展示了两种生长方式下晶体表面过饱和度时均分布云图及均方差,分析了不同转速、不同喷流速度、不同晶体尺寸对晶面时均过饱和度及均方差的影响。结果表明:相比于传统转晶法,喷流转晶法晶体的锥面过饱和度提高且表面均匀性增加。提高喷流速度可以进一步提高锥面过饱和度,但其均方差却呈现先减小后增大的变化。旋转速度的增加能提高锥面过饱和度并减小其均方差。此外,晶体尺寸也会在一定程度上影响喷流的效果。

Numerical Simulations of Flow and Mass Transfer in the KDP Growth System with Jet Rotating Crystal Method

A KDP crystal growth method which can improve the supersaturation of pyramidal face by j etting solution toward the apex of pyramid was introduced in this paper.The finite element method and the sliding grid technique were used to simulate the KDP crystal growth process of traditional rotating crystal method and jet rotating crystal method.The surface supersaturation distri-bution and standard deviation of supersaturation of two different growth methods were presented in this paper.In addition,the effects of different rotational speed,j et velocity and crystal size on supersaturation and standard deviation of supersaturation were analyzed. Compared with the traditional rotating crystal method,the supersaturation of pyramidal face was improved and the surface uniformi-ty was increased through jet-flow rotating crystal method.Increasing the jet velocity improved the supersaturation,while its standard deviation decreased at first and then increased.The increase of rotational rate can improve the supersaturation of pyramidal face and reduce its standard deviation.Furthermore,the crystal size also affected the effect of jet-flow in some degree.