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采用双流体模型(TFM)对一种新型整体式多喷嘴喷动-流化床内气固两相流动进行了数值模拟,在喷动床锥体两侧开若干侧喷嘴形成辅助多喷嘴结构,使其在喷动床锥体处产生喷动-流化效果,从而对环隙区锥体边界处堆积颗粒层产生扰流作用。通过CFD数值模拟获得了喷动床内颗粒速度及浓度的分布情况,并与单喷嘴喷动床模拟结果进行对比。研究并优化分析了不同侧喷嘴数量以及侧喷嘴宽度等关键参数对喷动床气固两相流动的影响规律。研究表明,与常规喷动床相比,整体式多喷嘴喷动-流化床结构能有效增强喷动床内环隙区颗粒相运动,特别是强化了喷动床环隙区底部流动死区的颗粒运动,使得锥体边界层颗的粒体积分数显著下降,颗粒体积分数沿径向分布变得更为均匀,同时省略了旁路供气辅助设备。
A two-fluid model (TFM) is used to simulate the gas-solid two-phase flow in a new type of integral multi-nozzle spout-fluidized bed. Several side nozzles are formed on both sides of the spout bed to form auxiliary multi- So that it can generate spout-fluidization effect in the spout bed conic body, and thereby disturb the accumulation of particle layers at the cone boundary of the annular zone. The distribution of particle velocity and concentration in the spouted bed was obtained by CFD numerical simulation and compared with the single nozzle spouted bed simulation results. The influences of the number of side nozzles and the width of side nozzles on the gas-solid flow in a spouted bed were studied and optimized. The results show that the integrated multi-nozzle spout-fluidized bed structure can effectively enhance the particle phase movement in the annular zone of the spouted bed, especially the dead zone at the bottom of the annular zone of the spouted bed, compared with the conventional spouted bed The particle volume fraction of the cone boundary layer significantly decreases, and the particle volume fraction becomes more uniform along the radial direction, while the bypass gas supply auxiliary equipment is omitted.