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Old   July 10, 2013, 01:42
Default suitable outlet boundary condition
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Govindaraju
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Dear all
In a pipe flow (many obstructions exist inside the pipe), If I don't know the outlet pressure, velocity etc what is the suitable boundary condition.
I know the inlet velocity and pressure at t=0 s
Kindly give your suggestions

Thank you

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Govind
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Old   July 10, 2013, 02:54
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there is now way to model a problem without knowing the outlet BC!.you can simplify the model to a known situation like free discharge flow or you can use a mas flow outlet BC.if you know the inlet velocity then you know the mass flow inlet that is equal to the mass flow outlet in most problems.
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Old   July 10, 2013, 04:24
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Quote:
Originally Posted by hmasenger View Post
there is now way to model a problem without knowing the outlet BC!.you can simplify the model to a known situation like free discharge flow or you can use a mas flow outlet BC.if you know the inlet velocity then you know the mass flow inlet that is equal to the mass flow outlet in most problems.
Thank you for your reply

I have one more question. Is outflow boundary condition equal to mass flow rate boundary condition?

Thank you

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Govind
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Old   July 10, 2013, 09:35
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yes but pay attention to flow dimensions. mass flow rate Is in kg/sec not m3/hr or other volume flow dimensions.
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