旋转室内铰刀三维参数对干法制备氮化硅颗粒性能的影响

Effects of the Three Dimensional Parameters of the Reamer in Rotary Cylinder on Properties of SiN Particles Prepared by Dry Granulation

为提高干法制备氮化硅颗粒的相关性能,分析铰刀三维参数对流场的影响,并通过扫描电子显微镜对颗粒球形度进行分析。构建欧拉气固两相流模型,针对不同铰刀三维参数设计三种物理模型,通过RNGk-ε模型对流场中的湍流情况进行求解,对比旋转室内颗粒体积分数分布的差异,并将数值结果与实验进行比照。云图分析表明旋转室内铰刀厚度分别为7mm、8mm、9mm时,氮化硅粉体平均轴向体积分数分别为0.36、0.30、0.33;氮化硅粉体平均径向体积分数分别为0.33、0.31、0.34;实验分析可知铰刀厚度为8 mm时,颗粒ρ值最高,并且流动指数最大,检验了数值模拟正确性。以上方法和结果对提高干法制备氮化硅颗粒性能有一定理论意义,并对铰刀三维参数设计提供一定依据。

In order to improve the properties of SiN particles prepared by dry granulation,the influence of the reamer’s three dimensional parameters on flow field is analyzed,and the particle sphericity is analyzed by SEM.The Euler gas-solid two-phase flow model is constructed.Three physical models for the granulation room are designed according to different bottom parameters.The turbulence in the flow field is solved by the modified RNG k-?model.The difference of particle volume fraction distribution in the granulation chamber is analyzed.The numerical results are compared with the experimental.The numerical results show that when the reamer’s thickness is 7 mm,8 mm and 9 mm,the axial particles volume fraction is 0.36,0.30 and 0.33 respectively,the radial particles volume fraction is 0.33,0.31 and 0.34 respectively.The experimental analysis shows that when the reamer’s thickness is 8 mm,the sphericity of the particles is the highest and the fluidity is the optimal,which verifies the correctness of the numerical simulation.The above methods and results have certain theoretical significance for improving the properties of SiN particles prepared by dry granulation,and provide some design basis of the reamer’s three dimensional parameters.