Abstract:

In this work, the mixing process and homogenization mechanism of Bi₂O-ZnO-B₂O₃ ternary glass slurry under mechanical excitation were numerically studied. Firstly, the dynamic viscosity of Bi₂O₃, ZnO and B₂O₃ glass slurries were measured by rotating viscometer and the particle sizes were measured by optical microscope. The diffusion coefficient of the slurries were obtained by Stokes-Einstein equation. Then, the simulation model for the mixing process of Bi₂O₃-ZnO-B₂O₃ ternary glass slurry under mechanical vibration is established by Fluent software, and the mixing deviation describing the mixing uniformity of ternary glass slurry is defined. The numerical results show that the increase of the amplitude and frequency of the container both accelerate the mixing of ternary slurry. The exciting amplitude and frequency should not be two large, otherwise, the slurries would overflow the container. Additionally, mixing deviation decreases with the increase of exciting time, which can be described by power function, so that the time required to mix uniformly for Bi₂O₃-ZnO-B₂O₃ ternary glass slurry under different amplitudes and frequencies can be predicted. Appropriate amplitudes and frequencies are helpful to improve mixing efficiency and avoid slurry overflowing the container.

Key words: bismuth-zinc-boron ternary glass slurry, numerical simulation, mixing process, homogenization mechanism

摘要：

通过数值模拟研究了机械振动下Bi₂O₃-ZnO-B₂O₃三元玻璃料浆的混合过程，并分析了混合均匀化机理。首先，利用旋转黏度计分别测量了Bi₂O₃、ZnO及B₂O₃三种玻璃料浆的黏度，并用光学显微镜分别观察三种玻璃料浆的粒度，通过Stokes-Einstein方程得到流体料浆的扩散系数。在此基础上建立了机械振动下Bi₂O₃-ZnO-B₂O₃三元玻璃料浆混合过程的Fluent模型，定义了描述三元料浆混合均匀程度的混合偏差。通过模拟研究发现：①增加容器振幅及频率均能加快三元料浆的混合；②机械振动的振幅及频率不宜过高，否则会导致料浆溢出容器；③混合偏差随时间增加而降低，可以通过幂函数描述，从而可以预测不同振幅和频率下Bi₂O₃-ZnO-B₂O₃三元玻璃料浆的混合均化时间。指出选择合适的振幅及频率，有助于提高混合效率，并避免料浆溢出容器。

关键词: 铋锌硼三元玻璃料浆, 数值模拟, 混合过程, 均匀化机理