A full-cycle numerical simulation of a circulating fluidized bed (CFB) by the use of the computational particle fluid dynamics (CPFD) method has been developed. The effects of the presence or absence of the secondary air, different secondary air positions, and different secondary air ratios on the gas–solid flow characteristics were explored. The results show that the presence of the secondary air makes a core-annular structure of the velocity distribution of particles in the fluidized bed, which enhances the uniformity of particles’ distribution and the stability of fluidization. The position and the ratio of the secondary air have a significant impact on the particle distribution, particle flow rate, and gas flow rate in the fluidized bed. When the secondary air position and ratio are optimal, the particles, particle flow rate, and air flow rate in the CFB are evenly distributed, the gas–solid flow state is good, and the CFB can operate stably.

中文翻译：

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计算粒子流体力学数值模拟铝土矿循环流态化焙烧过程中的气固流动

使用计算粒子流体动力学（CPFD）方法开发了循环流化床（CFB）的全循环数值模拟。探讨了是否存在二次风、不同二次风位置以及不同二次风比例对气固流动特性的影响。结果表明，二次风的存在使流化床内颗粒的速度分布形成芯环结构，增强了颗粒分布的均匀性和流化的稳定性。二次风的位置和比例对流化床内的颗粒分布、颗粒流量和气体流量有显着影响。当二次风位置和配比最佳时，CFB内颗粒、颗粒流量、空气流量分布均匀，气固流动状态良好，CFB能够稳定运行。