基于Euler-Euler模型的空气重介质流化床密度分布特性

Distribution characteristic of bed density in air dense medium fluidized bed based on the Euler-Euler model

以Geldart B类磁铁矿粉为主体加重质,采用试验测量与基于Euler-Euler多相流模型的数值计算相结合的方法,考察流化床沿床层高度方向和轴向的密度分布特性。结果表明:当操作气速控制在1.50Umf≤U≤2.20Umf时,床层密度沿床层高度方向与轴向位置的分布范围分别为1.95～2.10 g/cm3与2.00～2.10 g/cm3,两者的密度标准差均小于0.20 g/cm3。其中,轴向密度稳定性要高于床高方向密度稳定性,因此在实际分选过程中要侧重保持沿床高方向的密度波动性最小,进而提高流化床三维空间内的密度均匀稳定性,试验测量与数值模拟结果基本吻合。

With the selection of Geldart B type magnetite powder as medium solids,we investigated the density distri bution characteristic of the fluidized bed along the directions of bed heights and axial positions, by combining the ex perimental measurement and numerical simulation based on the EulerEuler multiphase model. The results indicate that the distribution range of bed densities along bed heights and axial positions are 1.952. 10 g/cm3 and 2. 00 2. 10 g/cmz respectively with the operating gas velocity of 1.50Umf 〈 U 〈2.20Umf, and the standard deviation both less than 0. 20 g/cm3. The density stability of axial positions is better than the density stability along different bed heights. Therefore, we should pay close emphasis to maintain the density fluctuation along bed heights as least as possi ble,which aims to improve the density stability in the whole ADMFB. It shows good agreements of the experimental measurement and numerical simulation results.