Experiments were carried out in geometrically similar vessels with diameters of 0.287, 0.495 and 1.1m respectively. Bubble diameter distribution was measured with a dual electric conductivity probe placed in the tanks...Experiments were carried out in geometrically similar vessels with diameters of 0.287, 0.495 and 1.1m respectively. Bubble diameter distribution was measured with a dual electric conductivity probe placed in the tanks. Gas holdup was measured by spillover method. Considering the coalescence of bubbles in the upper circulation region of the aeration stirred tank, introducing the concepts of turbulence decay and effective viscosity of gas-liquid system into this work, and taking into account the equilibrium between the surface energy of the bubbles and the energy supplied by agitation, mathematical models for bubble diameter and mean gas holdup were derived. The mathematical models were confirmed by experimental data.展开更多
The radial and axial distribution of mean 1iquid velocity were measured by a.hot-filmanemometer at the impeller region in an aerated and stirred tank 0.287m in diameter.The tangentialjet model for impeller discharge f...The radial and axial distribution of mean 1iquid velocity were measured by a.hot-filmanemometer at the impeller region in an aerated and stirred tank 0.287m in diameter.The tangentialjet model for impeller discharge flow used for single phase flow was modified to conform with thecharacteristics of gas-liquid flow.The radial and axial velocity profiles at the impeller region in thegas-liquid stirred tank were calculated by the model The results predicted by the model were in goodagreement with those obtained in experiment.展开更多
分析了气体分散通道叶片角度、搅拌转速、介质黏度、桨叶组合对气含率的影响.研究结果表明,当气体分散通道叶片角度为 30°时,在转速相同或输入相同的功率时,可以吸入更多的气体.气含率随搅拌转速和介质黏度的增大而增大.适宜的桨...分析了气体分散通道叶片角度、搅拌转速、介质黏度、桨叶组合对气含率的影响.研究结果表明,当气体分散通道叶片角度为 30°时,在转速相同或输入相同的功率时,可以吸入更多的气体.气含率随搅拌转速和介质黏度的增大而增大.适宜的桨叶组合为六直叶圆盘桨+六叶上斜叶桨,该组合具有较高的气体吸入速率和气体分散能力,气含率较高.气含率与单位体积功耗的关系为ε∝(P g /V)2.4,随单位体积功耗增大,气含率明显上升,气液分散效果更好,传质效率较高.展开更多
基金Supported by the National Nature Science Foundation of China.
文摘Experiments were carried out in geometrically similar vessels with diameters of 0.287, 0.495 and 1.1m respectively. Bubble diameter distribution was measured with a dual electric conductivity probe placed in the tanks. Gas holdup was measured by spillover method. Considering the coalescence of bubbles in the upper circulation region of the aeration stirred tank, introducing the concepts of turbulence decay and effective viscosity of gas-liquid system into this work, and taking into account the equilibrium between the surface energy of the bubbles and the energy supplied by agitation, mathematical models for bubble diameter and mean gas holdup were derived. The mathematical models were confirmed by experimental data.
文摘The radial and axial distribution of mean 1iquid velocity were measured by a.hot-filmanemometer at the impeller region in an aerated and stirred tank 0.287m in diameter.The tangentialjet model for impeller discharge flow used for single phase flow was modified to conform with thecharacteristics of gas-liquid flow.The radial and axial velocity profiles at the impeller region in thegas-liquid stirred tank were calculated by the model The results predicted by the model were in goodagreement with those obtained in experiment.
文摘分析了气体分散通道叶片角度、搅拌转速、介质黏度、桨叶组合对气含率的影响.研究结果表明,当气体分散通道叶片角度为 30°时,在转速相同或输入相同的功率时,可以吸入更多的气体.气含率随搅拌转速和介质黏度的增大而增大.适宜的桨叶组合为六直叶圆盘桨+六叶上斜叶桨,该组合具有较高的气体吸入速率和气体分散能力,气含率较高.气含率与单位体积功耗的关系为ε∝(P g /V)2.4,随单位体积功耗增大,气含率明显上升,气液分散效果更好,传质效率较高.
