通气式搅拌槽的传热特性

HEAT TRANSFER PROPERTIES IN AERATED AGITATED REACTOR

研究了通气式搅拌槽槽壁给热系数（ｈｗ）随通气速率和搅拌转速变化的规律和机理。在搅拌过程中存在一个临界转速，它决定了通气是增大还是减小ｈｗ。通过引入能综合反映操作条件对ｈｗ影响的无因次数Ｈｚ，获得了一个偏差较小并且简单实用的ｈｗ半经验关联式。

The heat transfer coefficient from the gas-liquid dispersion to the reactor wall was studied in an industrially practical agitated vessel.It was found that the effect of the presence of gas on the heat transfer coefficient was much more complicated than previous results.There was a critical impeller speed which determined how gas sparging changed the heat transfer coefficient.Operating conditions influenced on heat transfer interactively by three factors,which could be expressed by a dimensionless variable Hz. Based on theoretical analysis and experimental data,a new semi-empirical heat transfer correlation was proposed,which could be used in a wide range of operating conditions with good precision.