双流体模型中曳力及恢复系数对气固流动的影响  

Effects of Restitution Coefficient and Drag Force on Gas-solid Flow Behavior: A Two-fluid Model Simulation

作　　者：王嘉骏[1] 顾雪萍[1] 杨富军[1] 冯连芳[1] 

机构地区：[1]浙江大学化学工程与生物工程学系化学工程联合国家重点实验室聚合反应工程分室,浙江杭州310027

出　　处：《高校化学工程学报》2006年第2期164-168,共5页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金重大项目(20490200);国家重点基础研究专项经费资助(2005CB623804)。

摘　　要：应用双流体模型CFD模拟的方法,从恢复系数和曳力两方面,研究了气固密相流化床中颗粒之间和气固相之间的相互作用对床内非均匀流动结构形成与变化的影响。计算结果表明颗粒间非弹性碰撞和气固间曳力的增大均使气固两相流动的非均匀性增大。通过比较二者对非均匀流动结构的影响,发现气固间曳力是形成非均匀流动结构的决定因素。从碰撞耗散、颗粒动能和颗粒势能的角度分析了二者的作用机理,发现恢复系数和曳力对流动结构的作用主要区别在于对颗粒团聚和床层膨胀的影响程度不同。In the dense gas-fluidized beds, the heterogeneous flow structure of the gas-particle flow affects the gas-solid contact and transport process in the bed seriously. In order to explore the influence of the interactions between particles and between gas and particles on the formation of heterogeneous flow structure, a computational study was carried out by using a two-fluid model based on the particle kinetic theory, The results show that the stronger the particle-particle collisional dissipation and gas-solid drag force, the more heterogeneous the flow structure. It also shows that though the collisional dissipation dramatically intensifies the formation of heterogeneous flow structure, the gas-solid drag force is the fundamental factor which triggers the pattern formation. Based on the energy budget analysis of collisional dissipation, particle kinetic energy and particle potential energy, it shows that the main different between the effect of restitution coefficient and drag force on the heterogeneous flow structure is that the former effects the particle agglomeration chiefly and the later effects the bed height mainly.

关 键 词：气固流化床 双流体模型 非均匀流动结构 恢复系数 曳力 

分 类 号：TQ021.1[化学工程] TQ051.3