摘要
为了掌握湍流模型对喷动床内气、固2相流动特性的影响规律,采用双流体模型对喷动床内气、固2相流动行为进行了数值模拟研究。运用颗粒动理学理论描述颗粒相应力封闭流体控制方程,使用Gidaspow曳力模型描述气、固相间作用,将数值模拟结果与相关文献的实验结果进行了对比、验证,分析了3种湍流模型及颗粒碰撞恢复系数对喷动床内喷动形式、颗粒速度、颗粒体积分数及颗粒湍动能的影响规律。研究结果表明:湍流模型对喷动床的径向颗粒速度及孔隙率等参数的模拟结果影响不明显,但对喷动床内轴向流动的模拟结果,特别是喷射区及喷泉区内颗粒的体积分数和颗粒湍动能具有显著的影响,标准湍流模型下的床内颗粒湍动能在喷泉区最高,其体积分数云图也能较好地表现喷动的结构。颗粒碰撞恢复系数对喷动床内多相流动的数值模拟具有较强的敏感性,在数值模拟工作中需合理取值。
A eulerian-Eulerian two-fluid model in conjunction with the kinetic theory of granular flows was used for simulation of the spouted bed.The interaction between gas and particles was modeled using the Gidaspow drag model and the predicted hydrodynamic characteristics are compared with published experimental data.the effects of turbulence model and the coefficient of restitution of particles on hydrodynamic characteristics of spouted bed was investigated.Simulated results indicate that the hydrodynamic characteristics of axial direction in spouted bed is more sensitive to the different turbulence models compared to the Radial direction of spouted bed.Bed particle turbulent kinetic energy under standard turbulence model is the highest in fountain area,the contours of volume fraction performed the spouted structure better.The simulations results of hydrodynamic characteristics in spouted bed are sensitive to the value of coefficient of restitution of particles which should be appropriately given in simulation work.
出处
《中国科技论文》
CAS
北大核心
2015年第24期2909-2914,共6页
China Sciencepaper
基金
国家自然科学基金资助项目(21476181)
高等学校博士学科点专项科研基金资助项目(20136101120010)
中国博士后科学基金资助项目(2015T81048
2013M540768)
关键词
喷动床
湍流模型
颗粒恢复系数
数值模拟
spouted bed
turbulence model
coefficient of restitution of particles
numerical simulation
