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目前,针对气-固流化床的数值模拟多采用欧拉-欧拉双流体模型(TFM)。而传统的TFM基于均匀拟流体假设,不能准确描述流化床内流态化的非均匀性及介观尺度的性质,如颗粒团聚。本文采用基于能量最小多尺度方法(EMMS)的双流体模型(EFM)来研究聚乙烯流化床流体动力学,模拟结果证明EFM较好把握了流化床内的非均匀性以及介观尺度性质,更能准确描述聚乙烯流化床反应器内部的流体动力学。EFM模型的应用可以为聚乙烯生产过程中流化床结构改进以及“热点”的避免提供更有说服力的模拟验证。
At present, the Euler-Euler dual-fluid model (TFM) is mostly used for the numerical simulation of gas-solid fluidized bed. However, the traditional TFM can not accurately describe the fluidization heterogeneity and the mesoscopic scale properties, such as particle agglomeration, based on the hypothesis of uniform pseudofluid. In this paper, a two-fluid model (EFM) based on least-scale energy method (EMMS) was used to study the fluid dynamics of polyethylene fluidized bed. The simulation results show that EFM can better grasp the inhomogeneity and mesoscopic scale properties , More accurate description of the internal fluid dynamics of polyethylene fluidized bed reactor. The application of the EFM model can provide more convincing simulation validation of fluidized bed structural improvements and avoidance of “hot spots” in polyethylene production.