[dwsim-users] Shortcut Distillation: DWSIM 3 vs DWSIM 4

[Hector P. <hpe...@gm...>]

Hi Daniel,

I have set up shortcut distillations for a Sulfuric Acid - Nitric Acid -
Water system. However, I am getting very different results depending on
which version of DWSIM I use. I have checked that my settings are the same
in both simulations (NRTL constants and Inside-Out VLE flash algorithm).
DWSIM 3 predicts 21 minimum stages, whereas DWSIM 4 predicts only 3 stages.
I am running with a issue in DWSIM 3: it is not predicting the actual
number of stages (only predicts the minimum number) or the optimal feed
stage. Both of these values show NaN.

I would appreciate any insight here.

I still haven't gotten the rigorous columns to converge on these
simulations. If you have any tips here, I'd appreciate them.

I have attached 2 files, the first one (D3) is the DWSIM 3 file and the
second one is the DWSIM 4 file.

Thank you for your time,

Hector D. Perez