Calculation of liquid film thickness in falling film evaporators
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This post was last edited by ＆ Tears of Rainy Thoughts ＆ on 2019-11-8 at 16:02. The formulas for calculating film thickness found in different sources vary; I would like to know which one is correct! !
How did you think of calculating this? Could it be that the materials and components are different, which results in varying film thicknesses?
There is nothing wrong with the formula for calculating membrane thickness; it calculates in segments based on the Re value of the liquid film flow regime. That is, equation (10) represents the Nusselt theoretical solution under the assumption that the liquid film is in laminar flow and that the effect of gas-phase shear forces is ignored； Equation (11) is an empirical correlation for calculating the film thickness when the liquid film is turbulent, taken from Hidetaro Oobana’s \"Heat Exchanger Design Manual\".
For the same formula, in Eiichiro Oobana’s book it is “Re>1600”. The article is about “Re”