基于欧拉双流体模型和颗粒流动理论对实验室规模的循环流化床气化炉进行了全三维模拟,考察了炉内压力和固体颗粒的分布特征,并进一步比较了操作条件对炉内气固两相循环流动的影响差异.模拟结果表明:提升管内呈上稀下浓的颗粒分布,径向处存在边壁浓中心稀的环合结构,下降管内能够形成堆积较为密实的料封,模拟得到的系统压力环路与试验值较吻合.藏量、粒径和入口气速均会影响炉内的固体颗粒浓度和压力分布,合适的粒径和入口气速条件与颗粒终端速度的匹配是影响炉内稳定循环流化的关键因素.%Based on the Euler two-fluid model and particle flow theory,the full three-dimensional simulation is carried on a laboratoryscale circulating fluidized bed gasifier.The distribution of pressure and solid particles in the furnace is investigated,and the influence of operating conditions on gas-solid flow is further compared.The simulation results show that the solid particle distribution turn dilute upper and density lower in riser,and in radial direction turn core-annulus structure which is dilute in center and dense near wall side.A packing dense of material sealing is formed in the drop tube.The pressure loop simulated is in good agreement with the experimental value.The inventory,particle size and gas inlet velocity could influence the distributions of solid particle and pressure.Appropriate particle size and gas inlet velocity coupled with the particle terminal velocity are the key factors affecting the fluidized stability in the furnace.
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