【摘要】 基于稠密气固两相流流体动力学模型、颗粒动力学的颗粒湍动能模型 (KTGF)和气体湍动能模型(SGS) ,模拟计算结果得到了实验研究所揭示的环 -核流动结构 .模拟计算与Miller和Gidaspow的实验结果进行了比较 ,颗粒相浓度、速度和颗粒相动力黏性系数分布与实验值基本吻合 .更多还原

【Abstract】 Conservation of mass,momentum and fluctuation energy equations for solid and gas phases are used to compute the hydrodynamics of flow in a vertical riser. The present two phase flow model is derived starting from the Boltzman equation for velocity distribution of particles. The model is generated from the Navier Stokes equation,except that the solids viscosity and stresses are computed by simultaneously solving a fluctuating energy equation for the particulate phase. The turbulence of the gas phase is treated using a SGS turbulence closure model. A no slip boundary condition for the gas phase and slip boundary condition for the particulate phase are used. The model predicted the core annular flow structure in a riser,similar to that found experimentally in a dense gas solid flow. The predicted time averaged particle concentration,velocity and viscosity of particles are compared with the experimental data of Miller and Gidaspow and reasonable agreement is observed in a circulating fluidized bed. It is shown that the flow behavior is strongly affected by the plastic fluctuation energy,and the momentum and energy transfer between the particulate and the fluid constituents.更多还原