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Velocity Profile at inlet if Mass flow rate BC is given

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Old   January 28, 2016, 01:28
Question Velocity Profile at inlet if Mass flow rate BC is given
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Sing
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Hello Foamers and Researchers!!
Greetings!

I am quite new to OpenFoam, has been practicing it from last 1 month.
I have a doubt and I would be very grateful if anyone can help me with this.

In a problem I have given flowRateInletVelocity boundary condition at my inlet, specifying mass flow rate. fixedFluxPressure BC is given for pressure at the inlet. I want to know that if we give mass flow rate (or volumetric) BC then how the velocity profile at inlet will be decided? (Parabolic, uniform etc)

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Prateek.
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Old   January 28, 2016, 09:31
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Daniel P. Combest
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Prateek,

Seems you have double posted, so I'll answer both quickly to let the admin delete one if they like. Have a look at the code in

Code:
/src/finiteVolume/fields/fvPatchFields/derived/flowRateInletVelocity/flowRateInletVelocityFvPatchVectorField.C
there is a line in the updateCoeffs member function that says

Code:
        // mass flow-rate
        operator==(n*avgU/uniformRho);
This lets us know that it is a uniform velocity profile normal to the patch surface. The code is commented to let you know what is happening and look further in the .H file in the same directory for more guidance.
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Old   January 29, 2016, 02:52
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Hello Daniel,

Thanks a lot for the quick reply. I noticed afterwards that I posted this twice. Sorry for the same.

Yes I have seen the code as you mentioned and got what you said.

My deepest gratitude for sorting out my confusion.

Regards,
Prateek.
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Old   April 14, 2019, 21:03
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Hey guys,

Do you know how to set the mass flow rate NOT normal to the boundary?

B
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