【摘要】 采用大涡模拟(LES)方法模拟气相湍流,颗粒动理学方法考虑颗粒相碰撞产生的动量和能量传递和耗散,采用颗粒相大涡模拟方法(LESp)模拟颗粒脉动导致的能量耗散,同时考虑介观尺度对颗粒相压力的影响,建立了气体-颗粒LES-θ-LESp双流体模型,研究鼓泡流化床内气固两相流动的特性。数值模拟与文献实测颗粒速度和实测颗粒浓度结果具有相同的变化趋势。更多还原

【Abstract】 Flow behavior of gas and particles was modeled by means of the combination of the large eddy simulations for both gas phase and particles,and the kinetic theory of granular flow for particle collisions (LES-θ-LESp model).The sub-grid scale stress tensors of gas phase and particles were modeled based on the Smagorinsky model with different model constants.The momentum exchange and dissipation by particle collisions was considered by means of the kinetic theory of granular flow.The effect of meso-scale of particles on solids pressure and thermal conductivity was considered.The distributions of concentration and velocity were predicted in a bubbling fluidized bed.The effect of model constants on the distribution of velocity and concentration was discussed.Computation results were compared to experimental results of literatures for particle velocity and concentration of particles,and showed similar trends between simulations and experiments.更多还原