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题名	固体颗粒在反应器中悬浮机理的初步研究
作者	阎涵
学位类别	硕士
答辩日期	1998-06-30
授予单位	中国科学院研究生院
导师	毛在砂
关键词	多相反应 悬浮状态 层流 湍流
学位专业	无机化工
中文摘要	在化工过程中,常遇到液-固、气-液-固多相反应。在设计这些反应器时，最关键的问题通常是提高反应效率和能量利用效率。要解决这个优化问题，必须从研究固相颗粒在液相中的悬浮机理着手。在实际反应器中器底角落点一般为较难悬浮点，本文对二维和三维流场中反应器内角落点的颗粒悬浮进行了实验研究。在二维模拟反应器中针对平底反应器和截头锥底反应器两种类型、三种不同角落点的颗粒悬浮情况进行了实验研究。以圆柱颗粒作为二维研究对象，并且模拟反应器内三种角点的不同几何环境分别设计了槽形反应器，探讨了颗粒在反应器内的悬浮情况。实验中建立了一套的电化学测量-信号转换-微机采样系统，测量了角落点附近流场的底面剪切速率；以实验结果与理论预测进行了对比，检验了理论计算预测反应器内流场流动的可靠性；在综合理论与实验结果的基础上，讨论了随流场改变几种不同的颗粒悬浮形式，以及它们与流场底面剪切速率的对应关系。在反应器三维湍流流场中进行了单颗粒的悬浮实验。在不同操作形式（中心管上流、中心管下流）、不同几何尺寸的条件下，对两种粒径颗粒（粒径0.45mm、0.9mm)，分别测量了环流反应器的临界悬浮流量；初步探讨了不同条件下反应器内颗粒的悬浮规律；按实测的临界悬浮流量用计算流体力学程序计算了反应器内单相流场底面剪切速率值，得到了可作为预测不同流量下颗粒悬浮判据的流场特征值，并从理论上作了定性分析。
英文摘要	Multiphase reactors such as gas-liquid-solid and liquid-solid reactors are being widely used in industrial processes. The optimised design of chemical reactors is in general involved with a compromise of raising the reaction rate and reducing energy consumption. To solve the problem, mechanisms of solid suspension in reactors must be understood thoroughly. In the thesis, the experimental investigation on particle suspension is carried out in both laminar and turbulent flows. The corner point on the reactor bottom is usually the most difficult for particles to be suspended. Particle suspensions in the laminar flows in three kinds of corner environment of two types of two-dimensional reactors are investigated. In the experiments, a setup, including electrochemical measurement, signal A/D conversion and computer data acquisition, is established, and the wall on the bottom shear is measured. The computational predictions of wall shear are compared with the experimental data and the agreement is satisfactory. Based on the comprehension of the computational and experimental results, the correspondence between the different ways of particle suspension and the wall shear in the reactor is discussed. Suspension in turbulent flows in a loop reactor under different conditions, including two kinds of operation mode, four central tube sizes and two kinds of particles, is studied. The flow rate for critical suspension is recorded. The wall shear in different critical flow rate is calculated by the computational fluid dynamic method. The relation between the particle suspension near the corner point of reactors and the slope of the wall shear is discussed.
语种	中文
公开日期	2013-09-27
页码	82
内容类型	学位论文
源URL	[http://ir.ipe.ac.cn/handle/122111/2017]
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	阎涵. 固体颗粒在反应器中悬浮机理的初步研究[D]. 中国科学院研究生院. 1998.

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