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

[Daniel W. <dan...@gm...>]

Try this with the latest DWSIM 4 release (RC1). You won't be able to
reproduce the results from the shortcut column in a rigorous one because
your system is extremely non-ideal...

Daniel

2016-07-29 10:55 GMT-04:00 Hector Perez <hpe...@gm...>:

> Thanks Daniel. I'll be looking forward to the releases. I was trying to do
> it with ChemSep, but had some convergence issues with the column. I'll see
> if I can get one or the other to converge and use that one. Thank you.
>
> Hector D. Perez
>
> On Fri, Jul 29, 2016 at 9:40 AM, Daniel Wagner <dan...@gm...>
> wrote:
>
>> This is after applying the same fix to DWSIM 3:
>>
>> [image: Imagem inline 1]
>>
>> A final v3.7 build will be released together with DWSIM v4.0 with some
>> critical bug fixes for those who prefer v3. They can be installed
>> side-by-side on the same machine.
>>
>> Regards
>> Daniel
>>
>> 2016-07-29 10:36 GMT-04:00 Daniel Wagner <dan...@gm...>:
>>
>>> Hi Hector,
>>>
>>> The IO Flash algorithm was enhanced in DWSIM 4. There are a few
>>> additional checks to ensure convergence. In DWSIM 3 it is converging
>>> earlier than expected for your case.
>>>
>>> And you're still struggling with this system in DWSIM. You really should
>>> use ChemSep's column and thermo models through the CAPE-OPEN interface.
>>>
>>> Daniel
>>>
>>> 2016-07-29 10:08 GMT-04:00 Hector Perez <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
>>>>
>>>
>>>
>>
>