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基于欧拉-拉格朗日模型,气相采用LES湍流模型,固相采用离散颗粒法,同时考虑复杂气固流动以及相内、相间的化学反应,引入气化过程的热解反应模型,并且考虑了焦油的生成和均相转化,对流化床中可燃固体废弃物空气气化过程进行了三维数值模拟.获得了反应器内颗粒流型,气体组分浓度的分布规律以及不同操作条件下的产气组分、产气热值和焦油含量.结果表明:随着空气当量比ER的增加,CO、H2和CH4的体积分数逐渐减小,而CO2的含量逐渐增大.产气率随着ER的增加逐渐增大,产气热值逐渐减小,出口气中的焦油含量也随着ER的增加而明显减小.“,”A three-dimensional numerical model has been developed to simulate the combustible solid waste gasification in a fluidized bed.Based on the Eulerian-Lagrangian approach,the gas phase is modeled by the Large Eddy Simulation (LES) turbulent model and the solid phase is modeled by the discrete particle method.The complex particulate flow,mass and heat transfer,homogeneous and heterogeneous chemistry between phases and within the fluid mixture are considered.The pyrolysis of solid waste and the formation and homogeneous conversion of the tar are added to the previously established model.Particulate flow patterns,gas composition profiles,the total gas yield,gas heating value and the tar content in the exit gas at different equivalence ratio (ER) are investigated.The results show that concentrations of CO,H2 and CH4 decrease with the increasing ER,while the CO2 concentration gradually increases.The total gas yield increases with increasing ER,while the heating value of the gas reduces.The tar content of the exit gas dramatically decreases with the increasing ER.