气固循环流化床能量最小多尺度环核(EMMS/CA)模型

ENERGY-MINIMIZATION MULTI-SCALECORE-ANNULUS (EMMS/CA) MODELFOR GAS-SOLID CIRCULATING FLUIDIZED BEDS

通过对核区和环区分别建立相应的流体速度表达式改进了能量最小多尺度 (EMMS)径向流动模型 ,使模拟计算结果更趋合理 .将EMMS模型和环核 (CA)模型结合起来 ,建立了能量最小多尺度环核 (EMMS/CA)模型 ,通过EMMS模型的解可以使求解困难的CA模型得到封闭解 .运用该模型可以计算气固循环流化床中空隙率、流体速度、颗粒速度、滑移速度等动力学参数的二维分布 .

A modified energy-minimization multi-scale (EMMS) model is proposed through establishing different corresponding expressions for calculating radial profiles of gas velocity in core and annulus. The calculating results of the modified model are more reasonable than the previous model compared with the experimental results. A new model, called energy-minimization multi-scale core-annulus (EMMS/CA) model, is developed by combination of the EMMS and CA models. The equation of CA model can be solved via the solution of EMMS model. Two-dimensional distributions of dynamic parameters in gas-solid circulating fluidized bed, including voidage, fluid velocity, particle velocity, slip velocity and so on, can be calculated with the use of the present model. Comparisons with experimental data from literature confirmed the validity of the model.