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

[Hector P. <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
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>