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利用基于稀密两相结构的湍动流化床传质模型(基于结构的传质模型),结合稀密两相间的传质系数(相间传质系数)求解关联式对湍动流化床的传质行为进行了CFD模拟,以分析各关联式对模拟结果的影响。结果表明,采用以聚团为基础的Foka关联式求解相间传质系数时,基于结构的传质模型的模拟结果最好,而采用其他关联式的模拟结果均存在较大偏差,原因可能是反应主要发生在聚团相,并且相间传质系数求解关联式的特征结构与传质模型的基础结构不一致时会引入较大误差。随着气速增加,由于传质行为的强化,气穴相的臭氧浓度变化不大,而聚团相的臭氧浓度明显增加且主要发生在颗粒含量较少的床层上部。此外,还分析了传质行为与聚团尺寸的关系。
Based on the two-phase turbulent fluidized bed mass transfer model (structure-based mass transfer model) and the mass transfer coefficient (mass transfer coefficient between two phases) Mass transfer behavior of the CFD simulation to analyze the impact of the various correlations on the simulation results. The results show that the structure-based mass transfer model has the best simulation results when using the mass-based Foka correlation to solve the interphase mass transfer coefficient. However, the simulation results using other correlations have large deviations possibly due to the reaction Mainly occurs in the agglomeration phase, and the correlation between the mass-transfer coefficient and the mass-transfer model of the inter-phase mass transfer coefficient is inconsistent with that of the mass transfer model. With the increase of gas velocity, the concentration of ozone in the cavitation phase did not change much due to the enhancement of mass transfer behavior, while the ozone concentration of the agglomerated phase increased obviously and mainly occurred in the upper part of the bed with less particle content. In addition, the relationship between mass transfer behavior and agglomeration size was also analyzed.