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 kmgraju July 10, 2011 02:30

Transient flow

Dear all
My inlet is pulsatile pressure . since the inlet is pulsatile , I would like to introduce average mass flow rate at the outlet.

How to set average mass flow rate at the outlet as boundary condition

Thank you

 ghorrocks July 10, 2011 06:35

What feature do you have to absorb the pulses? Is it compressible flow? Free surface? FSI?

 kmgraju July 10, 2011 20:40

Quote:
 Originally Posted by ghorrocks (Post 315515) What feature do you have to absorb the pulses? Is it compressible flow? Free surface? FSI?
Dear

the flow is incompressible.I have a plan to do FSI as well . Thank you

 ghorrocks July 11, 2011 06:30

If you do not know what the average flow rate is then you probably should not use it as a boundary condition. In this case you probably know better what the pressure is, so use a pressure boundary instead.

 kmgraju July 11, 2011 11:39

transient flow

Quote:
 Originally Posted by ghorrocks (Post 315636) If you do not know what the average flow rate is then you probably should not use it as a boundary condition. In this case you probably know better what the pressure is, so use a pressure boundary instead.
Dear friend

The average flow is the variable at the outlet . so I may vary the flow . If the inlet pressure is pulsatile , The flow is also a pulsatile nature . Am I correct? if this is correct , I want to give average flow over the area . How to set up this boundary condition for this at the outlet ?

Thank you

Regards

Govind

 ghorrocks July 11, 2011 19:16

If you know the average flow then simply assign the exit to be a flow rate boundary with the average flow.

Be very careful that you have properly specified the boundary conditions. I recommend you read the CFX documentation on boundary condition specification to make sure you are heading in the right direction.

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