梯度磁场下气固流化床中磁颗粒运动数值模拟.pdf

第24 卷第1 期 高 校 化 学 工 程 学 报 No.1 Vol.24 2010 年 2 月 Journal of Chemical Engineering of Chinese Universities Feb. 2010 文章编号：1003-9015(2010)01-0052-06 梯度磁场下气固流化床中磁颗粒运动数值模拟 李 响, 孙 丹, 陈巨辉, 王 帅, 白颖华, 陆慧林 (哈尔滨工业大学 能源科学与工程学院, 黑龙江 哈尔滨 150001) 摘 要：在外加竖直方向梯度磁场的气固鼓泡流化床中，考虑铁磁颗粒受到的梯度磁场力和颗粒间磁感应力，对气相 采用流体力学方法(CFD)，颗粒相采用离散元法(DEM)，建立二维磁鼓泡流化床数学模型，模拟不同磁场强度下全磁颗 粒圆形床料的气固流动过程，分析了不同磁场强度对磁流化床中气泡生长、颗粒运动、床层压降和磁颗粒受力的影响。 研究结果表明在沿高度磁感应强度递减的梯度磁场中，磁颗粒在颗粒间磁感应力的作用下凝聚成链，破坏了大气泡的 形成。随着磁场强度增加，颗粒扩散系数减小，颗粒间磁感应力和梯度磁场力增大；气体与颗粒相间作用力先减小、 后增加；而颗粒接触力先增加、后减小。 关键词：梯度磁场；磁流化床；气固两相流；数值模拟；流体力学 离散元法 - (CFD-DEM) 中图分类号：O359.2 ；TQ051.13 文献标识码：A Numerical Simulation of Magnetic Particles Flow Behavior in a Gas-Solid Fluidized Bed with Gradient Magnetic Field LI Xiang, SUN Dan, CHEN Ju-hui, WANG Shuai, BAI Ying-hua, LU Hui-lin (School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, China) Abstract: Flow behavior of gas and solids in a two-dimensional magnetically assisted bubbling fluidized bed with whole magnetic balls under vertical gradient magnetic field was simulated. The motion of the gas was simulated by computational fluid dynamics (CFD), the particles were simulated by using discrete element method (DEM), and the effects of the magnetic strength in the fluidized bed with the additional magnetic field on the bubbling growing, motion of magnetic particles, gas pressure loss and interaction forces between particles were discussed. The simulation