摘要
基于数值模拟方法分析了几何相似旋风分离器在直径尺寸变化时的气相流场的模化特性。旋风分离器的直径变化范围为100～2100mm,重点考察流场量纲1速度分布的相似性、尺寸参数的自模特性。模拟结果表明,旋风分离器的直径尺寸变化后,流场的形态结构不变,但量纲1切向速度分布存在一定变化,流场不具有严格的自模性。但随直径尺寸的增大,旋风分离器内流场由弱自模性向强自模性发展,当直径超过2000mm后,流场量纲1速度基本保持相似与恒定,Euler数与Reynolds数不相关,流场处于强自模区。流场的这种自模特性反映了流场的惯性阻力损失和黏性摩擦损失之间的比例关系和大小变化。随着直径尺寸的增大,黏性摩擦损失系数减小,惯性阻力损失系数增大,但Euler数是减小的。当达到很大的直径时,Euler数恒定,Euler数与Reynolds数不相关,流场进入自模区,流场流态保持相似性。
The gas phase flow fields in the geometrically similar cyclone separators are simulated by Fluent 6.1.The cyclone diameter in the simulation ranges from 100 mm to 2100 mm.Based on the simulation results,the effect of cyclone size parameters on the dimensionless velocity similarity is investigated.The results show that the flow fields are similar for different cyclone diameters,but the dimensionless tangential velocities are different.Hence,the flow field is not strictly similar.As the cyclone diameter increases,the flow field develops from weak similarity to strong similarity.When the cyclone diameter is more than 2000 mm,the dimensionless velocities are constant,indicating that the Eu number is not affected by Re number and the flow field is in self-similarity.The self-similarity of the flow field reflects the contribution of the inertia resistance loss and viscous friction loss to the total energy loss.As the cyclone diameter increases,the viscous friction loss decreases while the inertia resistance loss increases,but the Eu number decreases.When the cyclone diameter increases to some value,Eu number is independent of Re number,and the flow field is in self-similarity.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2010年第9期2274-2279,共6页
CIESC Journal
基金
国家自然科学基金项目(20906100)
国家高技术研究发展计划项目(2007AA061702)~~
