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应用粒子动态分析仪,对方形管循环流化床的稳定段颗粒相的流动结构进行了实验研究。颗粒浓度呈中心稀、壁面附近浓,且边角效应明显;颗粒速度的垂直分量中心向上,壁面附近向下,水平分量则指向壁面和角落。颗粒浓度和速度分布特性证实了方形管环核结构的存在。颗粒相的湍流脉动量随着向壁面的靠近而降低,且表现出显著的各向异性特点。湍流相关脉动量在床中心大,边壁低,且在床的中心区域呈现出各向异性而在边壁区则表现出各向同性的特点
The particle structure of the stationary phase in a square tube circulating fluidized bed was studied experimentally by particle dynamic analyzer. Particle concentration center dilute, concentrated near the wall, and the corner effect is obvious; particle velocity vertical component of the center up, near the wall down, the horizontal component points to the wall and corner. Particle concentration and velocity distribution characterize the existence of a square ring nucleus structure. The turbulent pulsation of the particle phase decreases with the approach to the wall, and shows significant anisotropy. Turbulence-related pulsations are large in the center of the bed, low in the side walls, anisotropic in the central region of the bed, and isotropic in the sidewall region