鼓泡塔中的有效涡扩散系数及湍流特性

EDDY DIFFUSIVITY AND TURBULENT STRUCTURES IN BUBBLE COLUMNS

依据湍流模式理论提出新的有效涡扩散系数关系式，讨论其与既有关系式的异同并与湍流实测数据比较，结果表明，本文关系式给出与实测值更为一致的结果，而既有的一些关系式的计算值偏高．由此讨论了涡扩散系数与鼓泡塔流动模型的关系，指出了数据偏差产生的原因．

Based on the Turbulence Model Theory,a new model for prediction of buld average eddy diffusivity in bubble columns was developed.Comparison of the model results with experimental data available showed that the new relation gave a reliable estimate of the eddy diffusivity,while reported some relations overestimated the eddy diffusivity.Furthermore,the relationship between the turbulence closure procedure and the simplified circulation flow model adopted by many researchers was discussed to explain possible ressons for the above discrepancy.