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#1 |
New Member
Aditya
Join Date: Dec 2011
Posts: 28
Rep Power: 14 ![]() |
Hi,
I have a mixture of 55% xenon, 35% hydrogen and 15%oxygen by mass fraction in a bubble surrounded by nitrogen medium. By calculating the density using ideal gas the denisty of bubble should be greater than the density of nitrogen but the bubble turns out to be less denser than the surrounding nitrogen medium. I have a UDF for specifying mass fractions and when I have only Xe and oxygen the bubble is denser than nitrogen but the moment hydrogen is added (even as little as 0.01 mass fraction), the bubble goes way below the density of surrounding nitrogen. SETUP: DRIVEN SECTION OF TEH SHOC TUBE WITH NITROGEN AS THE SHOCK TUBE AND A BUBBLE AT THE CENTER. someone please help. |
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#2 |
New Member
Mohammad Ghazvini
Join Date: Mar 2010
Posts: 16
Rep Power: 16 ![]() |
Maybe that problem will resolve if you increase the number of grids.
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#3 |
New Member
Aditya
Join Date: Dec 2011
Posts: 28
Rep Power: 14 ![]() |
do you think resolving the mesh would help the calculation of density?
im just curious. I will try everything to fix this problem. but can you just outline ur thought process. |
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#4 |
New Member
Mohammad Ghazvini
Join Date: Mar 2010
Posts: 16
Rep Power: 16 ![]() |
Yes it will sometimes.
in gas mixtures averaging causes problems, so the larger is the grid size, the larger is the averaging effect. |
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#5 |
New Member
Aditya
Join Date: Dec 2011
Posts: 28
Rep Power: 14 ![]() |
sounds good. I will try the mesh refinement and will let yoou know immeditaely.
Thanks a lot once again for the advice. |
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#6 |
New Member
Aditya
Join Date: Dec 2011
Posts: 28
Rep Power: 14 ![]() |
hey,
I have tried refining the mesh but it didnt work. Can you suggest me some other idea for the problem.? |
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