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Old   November 24, 2015, 18:36
Default Pressure boundary conditions
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Martin Nolan
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Hi all,

I need to calculate flow rate from a 2d pipe. The 'total' pressure difference between inlet and outlet is only 1 pascal. The pressure inlet be asks me to define total gauge pressure, which is fine. However outlet says only gauge pressure - I presume static pressure. Using a value of 1 pascal less than the inlet BC does not give me accurate results vs theoretical results. Can anyone advise?

Thank you
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Old   November 25, 2015, 02:47
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hi mate,
pressure outlet is static pressure for flow going out of domain.
do you have any reverse flow?
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Old   November 25, 2015, 03:28
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Quote:
Originally Posted by sadjad.s View Post
hi mate,
pressure outlet is static pressure for flow going out of domain.
do you have any reverse flow?

I have no reverse flow

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Old   November 25, 2015, 03:54
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try using velocity inlet and then calculate delta P across domain.
how much is your error?
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Old   November 25, 2015, 04:12
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Quote:
Originally Posted by sadjad.s View Post
try using velocity inlet and then calculate delta P across domain.
how much is your error?
The delta P must be 1 :/ the error is 5 orders of magnitude as well...
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Old   November 25, 2015, 09:22
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Is there anyway I can ensure that the Total pressure difference between the inlet and outlet is 1Pa? I seem to be getting big changes in pressures
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