CAJ | 학술논문

建立了单喷管鼓泡流化床欧拉-欧拉双流体模型,分别采用标准k-ε湍流模型、RNGk-ε湍流模型和Realizable k-ε模型对平板、斜板和U形板流化床进行数值模拟计算.结果表明,标准k-ε模型和RNG k-ε模型模拟计算结果与实验结果吻合较好.床层固体颗粒浓度分布呈以下规律:在气体主要流经的中心区域颗粒浓度较低,而在靠近壁面区域颗粒浓度相对较高.3 种分布板结构流化床中心区域颗粒轴向速度为正值并且较大,颗粒向上运动;靠近壁面附近区域颗粒轴向速度为负值,做下降运动,产生了"环-核"流动现象.与平板流化床相比,斜板和U形板流化床的横向运动速度更大,容易形成循环运动.
건립료단분관고포류화상구랍-구랍쌍류체모형,분별채용표준k-ε단류모형、RNGk-ε단류모형화Realizable k-ε모형대평판、사판화U형판류화상진행수치모의계산.결과표명,표준k-ε모형화RNG k-ε모형모의계산결과여실험결과문합교호.상층고체과립농도분포정이하규률:재기체주요류경적중심구역과립농도교저,이재고근벽면구역과립농도상대교고.3 충분포판결구류화상중심구역과립축향속도위정치병차교대,과립향상운동;고근벽면부근구역과립축향속도위부치,주하강운동,산생료"배-핵"류동현상.여평판류화상상비,사판화U형판류화상적횡향운동속도경대,용역형성순배운동.
An Euler-Euler two-fluid model for single nozzle bubbling fluidized bed was established,and numerical simulations for fluidized beds with flat plate,inclined plate and U-shaped plate were conducted using standardk-εmodel,RNGk-ε model and Realizablek-ε model,respectively.The results show that the numerical simulation re-sults by standardk-ε model and RNGk-ε model agreed well with the experimental results.The distribution regularity of solid particle concentration in beds was as follows:the particle concentration in the central area where most of the gas flowed through was low,while that in the areas close to the walls was relatively high.For the three distribution plates in the study,the particles in the center had a positive velocity and moved upwards,while those close tothe walls had a negative velocity and moved downwards,thus resulting in the "ring-core" flow phenomena.Compared with the flat bed,the lateral velocity for inclined plate and U-shaped plate fluidized beds was higher,which was more likely to generate circular motion.