Multiphase reaction model based on bubble structures in bubbling bed

doi:10.11949/j.issn.0438-1157.20180020

Abstract

Abstract:

Gas-solid bubbling beds embrace complexity coupled by flow, heat/mass transfer and reactions over a wide range of spatial-temporal scales, which meso-scale flow structure, e.g., bubble, plays a critical role on gas-solid transfer. It is necessary to build meso-scale model on the basis of reasonable physical simplification of real processes, for accurate interpretation of heat/mass/momentum transfer and reaction in gas-solid flow systems. A multi-fluid reaction model from bubble structures was proposed with a consideration of effects of non-uniform meso-scale structure on gas-solid reaction in bubbling bed. Further, the mass transfer and reaction model in the two fluid model (TFM) was modified by a defined heterogeneity reaction index, which made the model easier to use. Model was validated through simulation of ozone catalytic decomposition in bubbling bed, showing good agreement with literature data.

Key words: multiphase flow, meso-scale, EMMS, fluidized-bed, ozone decomposition

摘要：

气固鼓泡床是一个流动、传热/传质和反应多尺度时空耦合的复杂系统。其中介尺度流动结构（如气泡）对于气固相间传递起着关键性的作用。为了准确描述气固流态化系统中的“三传一反”行为，需要在合理物理简化的基础上建立介尺度模型。提出了基于气泡结构的多流体反应模型，考虑了介尺度非均匀结构对于鼓泡床内气固相间反应的影响；定义了基于气泡的反应非均匀因子修正双流体（TFM）传质反应模型，从而使模型更加易用。通过鼓泡床内的臭氧催化分解反应模拟，对模型进行了初步验证，模拟结果与文献结果相符。

关键词: 多相流, 介尺度, EMMS, 流化床, 臭氧分解

CLC Number:

TQ032.4

LIU Cenfan, ZHANG Nan, WANG Wei. Multiphase reaction model based on bubble structures in bubbling bed[J]. CIESC Journal, 2018, 69(5): 2057-2062.

刘岑凡, 张楠, 王维. 鼓泡床中基于气泡结构的多相反应模型[J]. 化工学报, 2018, 69(5): 2057-2062.

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