Gas blender Toolkit, wrong calculation?

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Thank you, so I do want a real gas model.

Baltic blender does not work, that's bad.

Any other software which can calculate my problem and has a real gas model?
 
Any other software which can calculate my problem and has a real gas model?

A while back I wrote Yet Another Gas Mix Calculator (YAGaMiC) in MS Excel using macros and the goal seek function, which shows the same gas mix calculation using three different methods - Ideal Gas Laws; Van Der Waals and GERG-2004.

Most software calculating van der Waals (including mine) uses the 'Atomox' equation to calculate the compressibility of a gas mixture and sadly this approach is not fully correct. The most accurate approach is GERG (Groupe European de Recherches Gazires) equation of state (EOS) .

It so happens that my spreadsheet is able to solve blending using up to two preblended gas mixtures and air e.g. EAN / Trimix (rather than pure He / O2). If I understood your needs the GERG result is as follows:

Start 29/0 @ 150 Bar
Add 34/0 +70.2 Bar
Add Air +49.8 Bar
Result 29/0 @ 270 Bar

I am happy to share the spreadsheet 'as-is' and it is here for you to download. Being macro based it will not work in open office, only MS Excel
 

Attachments

  • YAGaMiC 2016 v2 (2.3).xls
    1 MB · Views: 168
@MadUKDiver, thank you very much, looks great indeed!

I've never heard about GERG - Groupe Européen de Recherche Gazière. Most accurate approach sounds perfect.

Unfortunately I have a problem using this great excel sheet. I open in MS Excel, press activate..... I can play around, get results which seem to be OK but only in ideal gas and Van der Waals, not in GERS. Right from the beginning GERS is giving NV, see pic.

I am not the it expert at all, thanks for help.
IMG_6272.jpg
 
@Agro I can't repeat that problem but the workbook uses the Excel "Solver Add-in" so I suggest checking if that is enabled. Within Excel go to File, Options, Add-ins and if necessary load and enable the Solver Add-in

2021-11-07_105047.jpg
2021-11-07_104705.jpg
 
This did not work on my PC. My it expert sais the excel is working on his PC, so the problem seems to be on my computer. He will check this.
 
A while back I wrote Yet Another Gas Mix Calculator (YAGaMiC) in MS Excel using macros and the goal seek function, which shows the same gas mix calculation using three different methods - Ideal Gas Laws; Van Der Waals and GERG-2004.

Most software calculating van der Waals (including mine) uses the 'Atomox' equation to calculate the compressibility of a gas mixture and sadly this approach is not fully correct. The most accurate approach is GERG (Groupe European de Recherches Gazires) equation of state (EOS) .

It so happens that my spreadsheet is able to solve blending using up to two preblended gas mixtures and air e.g. EAN / Trimix (rather than pure He / O2). If I understood your needs the GERG result is as follows:

Start 29/0 @ 150 Bar
Add 34/0 +70.2 Bar
Add Air +49.8 Bar
Result 29/0 @ 270 Bar

I am happy to share the spreadsheet 'as-is' and it is here for you to download. Being macro based it will not work in open office, only MS Excel
great work
 
My it expert is working on it. Until then could you please do my a favour by calculating this?
EAN29, 100 bar
Top off by EAN34 and air
Result: EAN29, 270 bar

Thank you very much, great forum, great members here!
 
My it expert is working on it. Until then could you please do my a favour by calculating this?
EAN29, 100 bar
Top off by EAN34 and air
Result: EAN29, 270 bar

Thank you very much, great forum, great members here!
you're adding between 93 and 104bar of 34% before the air top
 

Attachments

  • 199143891aa84f9c17492bae066780f9.png
    199143891aa84f9c17492bae066780f9.png
    72 KB · Views: 76
Great, thank you very much.

Now let's talk about
- ideal gas calculation: does not work on high pressure
- Van der Waals
- GERG

Until now I only knew ideal gas and Van der Waals. I thougt that Van der Waals is equal to real gas calcualtion. Now we were told, GERG is better than Van der Waals, so far so good. And very good to know.

As far as I know there is no other gas blender tool that uses GERG. They all say "real gas" and work with Van der Waals. Or am I wrong?
 
My it cunsultant tried to make the excel work on his PC, it did not. He is asking: on which excel version does it work? He saw something like 2016.

Does it only work on 2016 or older?

Sorry for my question, I am not the expert at all.....
 
https://www.shearwater.com/products/perdix-ai/
http://cavediveflorida.com/Rum_House.htm

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