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题名	下行床弧面气固快速分离器的实验和数值模拟
作者	都林
学位类别	硕士
答辩日期	2003
授予单位	中国科学院过程工程研究所
授予地点	中国科学院过程工程研究所
导师	姚建中
关键词	气固快速分离 下行床反应器 相位多普勒颗粒分析仪 数值模拟
其他题名	Experimental and Numerical Study of A Rapid Gas-Solid Separator with Cambered Surface for Downer Reactor
学位专业	化学工艺
中文摘要	自从二十世纪七十年代以来,下行床快速反应器在石油流化催化裂化、煤粉和生物质的热解等领域已得到了越来越多的重视.对于这些快速反应过程,气固快速分离是非常必要的.传统的分离手段已不再适用.中国科学院过程工程研究所最近提出了一种新型的弧面气固快速分离装置.为了考察该分离器的分离性能、影响因素和揭示气固分离机理,该文从实验和计算两个角度对该分离器进行了研究.采用FCC物料进行了分离器分离性能实验,操作气速、颗粒加料率和分离器几何结构参数影响了分离器的分离效率和压降损失,分离器的结构需要进行优化.采用先进的二维相位多普勒颗粒分析仪(PDPA)对分离器内颗粒的流动进行了测量..测量得到了颗粒的速度分布、体积通量分布和粒度分布.分析表明分离器内构件包括喷嘴、弧面和挡板对分离起了重要作用,颗粒通过气固的惯性差别以及与弧面、挡板的碰撞作用实现分离.不同粒径的颗粒由于Stokes惯性参数的不同表明出不同的运动行为.测量加深了对分离器颗粒运动和机理的认识.采用通用计算流体力学软件FLUENT软件包对分离器内气固两相流动进行了数值模拟.对连续相(气相)采用欧拉坐标下的标准的k-ε双方程模型,对离散颗粒相采用拉格朗日坐标下的离散颗粒轨道模型.计算进行了灵敏性分析,对两种典型的分离器内的气固两相流动进行了数值模拟和分离效率计算,计算结果与实验测量趋势一致,说明采用计算的方法是可行的,为分离器结构的进一步优化提供了工具.
英文摘要	Since the 1970s, more and more attention has been paid to short contact time gas-solid downer reactor in such chemical processes as fluidized catalytic cracking of hydrocarbon, pyrolysis of pulverized coal and biomass. For these processes gas-solid rapid separation is indispensable, yet hardly feasible for traditional separators. A new rapid gas-solid separator with cambered surface was proposed by the Institute of Process Engineering, Chinese Academy of Sciences. To investigate the separation performance of the newly developed separator and to understand its separation mechanism, experiments were carried out and computational analysis was performed in the work. Results from particle separation tests using FCC particles were presented. Gas velocity, solids loading rate and separator geometrical parameters were factors affecting separation performance including collection efficiency and pressure loss. Optimization of the separator geometrical parameters was needed. Particle flow patterns inside the separator were measured by using two-dimensional Phase Doppler Particle Analyzer (PDPA). Particle velocity, volume flux and size distribution were obtained. It had been found that the internal structure including the rectangular nozzle, the circular arc camber and the baffles played important roles in the gas-solids separation process. Particles were separated from gas phase due to difference of inertia between gas and solid and collision of particles with the internal structure. Performance variation for different size particles was found to dependend on the dimensionless stokes number. PDPA measurements provided a deep insight into particle motion and separation mechanism of the new separator. Numerical simulation of gas-solid two-phase flow in the separator was performed with the general-purpose computational fluid dynamics (CFD) software package FLUENT 6.0. Standard k- e turbulent model based on the Eulerian approach was adopted to simulate the continuous phase (gas) flow, and discrete particle trajectory model based on the Lagrangian approach was used to calculate the particulate phase. Sensitivity analysis of modelling parameters was performed and gas-solid flows in two typical separators were simulated. Separation efficiency was calculated and the predicted results were in agreement with experimental measurements, suggesting that CFD is a useful tool for modeling and optimization of the new separator.
语种	中文
公开日期	2013-09-16
页码	108
内容类型	学位论文
源URL	[http://ir.ipe.ac.cn/handle/122111/1366]
专题	过程工程研究所_研究所（批量导入）
推荐引用方式 GB/T 7714	都林. 下行床弧面气固快速分离器的实验和数值模拟[D]. 中国科学院过程工程研究所. 中国科学院过程工程研究所. 2003.

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