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November 22, 2010, 11:23 |
Total mass flow
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#1 |
New Member
Enio Carpi
Join Date: Apr 2010
Posts: 12
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Hi Folks
I'm simulating a chamber pumpdown using a getter. The pumpdown speed depends on the total mass sorbed by the getter (I have the model for that). What would be the variable for the cumulative mass flow through an outlet? Or would it be possible to integrate over time? thx for the help |
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November 22, 2010, 17:00 |
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#2 |
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Join Date: Feb 2010
Location: Australia
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You could do a numerical integration via a CEL expression. Not sure on the variable though - I have no knowledge in this area.
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November 22, 2010, 18:29 |
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#3 |
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Glenn Horrocks
Join Date: Mar 2009
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Sorry, but no. You cannot do time integrals in CEL. If you have to do time integrals you will need to do it in fortran.
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November 22, 2010, 18:57 |
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#4 |
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So CFX does not have an internal time value that can be used/addressed?
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November 22, 2010, 19:10 |
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#5 |
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Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
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Yes, CFX does have a time value. But CEL values do not persist between time steps so there is no way to accumulate over time. You could make a fortran CEL function to do the accumulation over time and normal CEL to do everything else. This is not too hard to do.
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November 23, 2010, 06:41 |
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#6 |
New Member
Enio Carpi
Join Date: Apr 2010
Posts: 12
Rep Power: 16 |
Thanks for the comments. So, it seems I'm stuck here. I'll work on something. Thank you again
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November 24, 2010, 12:59 |
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#7 |
New Member
Enio Carpi
Join Date: Apr 2010
Posts: 12
Rep Power: 16 |
So fa rthe only solution is to use "mass()@domain". The total mass out of the domain is initial mass - mass()@domain. It seems to work. Now I just need the folks from SAES to send me some data.
Take care |
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