双循环流化床颗粒分布特性的三维数值模拟

3D computational simulation of solid distribution characteristics in dual circulating fluidized bed

基于欧拉多相流模型对双循环流化床内气固流动进行三维数值模拟.结果表明:空气反应器与燃料反应器内x轴方向径向颗粒浓度分布均因连通结构的影响而具有明显不对称性.改变燃料反应器流化气量,x轴正向近壁面区域颗粒浓度随流化气量的增加迅速减小并在流化气量达到12.5 m3/h后趋于稳定,x轴负向近壁面区域颗粒浓度随流化气量先增大后减小随后再次增大,而z轴正向与负向近壁面区域颗粒浓度随流化气量增大而减小.

Three dimensional computational simulation based on Euler multiphase flow model was carried out for the gas-solid flow in dual circulating fluidized bed. The results suggested that the solid distributions along x-axis direction in both air reactor （AR） and fuel reactor （FR） showed obvious asymmetry due to the influences of connecting structures. The solid concentration in the near-wall region in x-axis positive direction in FR decreased rapidly with FR fluidization rate and the trend became stable after FR fluidization flow rate reached 12.5 m^3/h. Meanwhile, the solid concentration in the near-wall region in x-axis negative direction increased first and then decreased. The solid concentration in the near-wall regions in both z-axis positive and negative directions in FR decreased with FR fluidization flow rate.