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

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

Hi Hector,

DWSIM 4 is faster but not THAT fast. Maybe it is something specific to your
case that was "accidentally" optimized...

2016-08-02 16:45 GMT-04:00 Hector Perez <hpe...@gm...>:

> Hi Daniel,
>
> I've downloaded the new DWSIM 3.7 and 4.0. I was wondering if you could
> tell me why DWSIM 4 is so much faster (it does 1000 iterations in a
> Distillation column in a split second, whereas DWSIM 3 takes a long time
> [minutes])?
>
> Thanks
>
> Hector D. Perez
>
> On Fri, Jul 29, 2016 at 10:32 AM, Daniel Wagner <dan...@gm...>
> wrote:
>
>> Release Candidate 1 (RC1) was released yesterday =>
>> https://sourceforge.net/projects/dwsim/files/DWSIM/DWSIM%204.0/DWSIM_bin_v40_RC1.exe/download
>>
>> Add your user.pcd file to the main Chemsep PCD file and you'll be able to
>> run the simulation I've attached earlier.
>>
>> 2016-07-29 11:23 GMT-04:00 Hector Perez <hpe...@gm...>:
>>
>>> Is the RC1 release the same as Preview 4?
>>>
>>> I have attached the ChemSep pcd file that has H2SO4.
>>>
>>> Thanks, Daniel. This is an interesting system. From what I've gathered
>>> from literature, H2SO4 is used to break the Nitric acid/water azeotrope to
>>> improve the nitric acid recovery.
>>>
>>> Hector D. Perez
>>>
>>> On Fri, Jul 29, 2016 at 10:09 AM, Daniel Wagner <dan...@gm...>
>>> wrote:
>>>
>>>> I've created a simulation with a ChemSep column but it doesn't have
>>>> Sulfuric Acid on its database. Maybe you could add it using the PCD Manager.
>>>>
>>>> 2016-07-29 11:01 GMT-04:00 Daniel Wagner <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:
>>>>>>>
>>>>>>>
>>>>>>> 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
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>