单层桨气液搅拌釜的气液分散特性

Gas-Liquid Dispersion Characteristics of Gas-Liquid Stirred Tank with Single-Layer Impeller

在计算流体力学数值模拟的基础上,对单层桨气液搅拌釜的气液分散特性进行研究。考察进气方式、介质黏度和单位体积功耗对气含率及功耗性能的影响。实验结果表明,气含率随介质黏度的增大而减小;在相同的单位体积功耗时,自吸分散的气含率高于表面充气分散的气含率;与表面充气分散相比,自吸分散的单位体积功耗和功率准数均低;与标准搅拌釜相比,单层桨气液搅拌釜的气含率分布均匀,气液分散效果更好,单位体积功耗低,达到相同分散效果时的搅拌转速低。

The gas-liquid dispersion characteristics of a gas-liquid stirred tank with single-layer impeller were studied based on the computational fluid dynamics numerical simulation.The influences of intake ways and medium viscosity on the gas holdup and power consumption were investigated.The results showed that,the gas holdup decreased with increasing medium viscosity,and in the same unit volume power consumption the gas holdup of self-priming dispersion was higher than that of surface aeration dispersion.The unit volume power consumption and power number of the self-absorption dispersion are lower than those of the surface aeration dispersion.Compared with a standard stirred tank,the unit volume power consumption of the stirred tank with single-layer impeller was reduced and the same dispersion effect could be achieved at lower stirring speed.