Fundamental Study on the Stirring of Liquid Iron and the Liquid-Liquid Mass Transfer in Gas Injection System.

为了获得铁液搅拌和注气液液传质的基本知识，进行了水模型实验并对其进行了分析。体系内流动：在氮气搅拌的水-苯体系中，观察了水中的流动模式和液滴形成的外观。证实了水中存在较大的再循环流量，并且随着气流量的增加，苯滴中苯的数量增加。液液传质：测定了在不同的气流量、苯与水的高度、容器半径等条件下苯乙酮从苯向水的传质速率。结果与低气流量和高气流量两个经验方程相关。在高气流量下，由于苯液滴的形成，气流量对体积系数<k_LA>的影响非常大。利用低气流量条件下的经验方程，结合液滴在水中的体积和平均直径的测量结果，估算了液滴形成的贡献。<k_LA>的计算值与观测值吻合较好。系统湍流特性：湍流分析系统由热线风速仪和FFT分析仪组成，用于测量时间平均速度分布和湍流运动能量。该系统还用于湍流功率谱的分析。研究发现，当前系统的湍流特征与各向同性湍流非常相似。流动模拟：采用最基本的湍流模型——0方程模型，估计了局部气含率和流型的时均分布。

Model experiments by the use of water and its analysis were made in order to obtain fundamental knowledge on the stirring of liquid iron and the liquid-liquid mass transfer by gas injection.1. Flow in the system: Flow pattern in water and appearance of droplet formation were observed in the water-benzene system stirred by nitrogen. The existence of large recirculating flow in water and the increase in number of benzene of benzene droplets with gas-flow rate were confirmed.2. Liquid-liquid mass transfer: Transfer rate of acetophenone from benzene to water were measured under the various conditions of gas-flow rate, the height of benzene and water, and the radius of vessel. The results were correlated by two empirical equations-at low gas-flow rate and at high gas-flow rate. At high gas-flow rate, the effect of gas-flow rate on the volumetric coefficient, <k_LA> , was very large because of the benzene-droplet formation. Contribution of droplet formation was estimated by using the empirical equation at low gas-flow rate and the measured results of the amount of droplet in water and its average diameter. Calculated values of <k_LA> agreed well with observed ones.3. Characteristics of turbulence in the system: Turbulence-analysing system composed of a hot wire anemometer and a FFT analyser was used for the measurements of the distributions of time-averaged velocities and the turbulent kinematic energies. This system was also used for the analysis of power-spectrum of turbulence. It was found that the characteristics of turbulence in the present system was very similar to those of the isotropic turbulence.4. Simulation of flow: The 0-equation model which is the most fundamental model of turbulence was used for the estimation of the time-averaged distributions of local gas holdup and flow pattern.