Is it possible to have an actual velocity profile at the inlet with pressure-inlet BC

hanis_iz · December 15, 2018, 02:04

I am doing research on airflow condition in airways. Is it possible if I set the inlet's boundary condition as pressure-inlet but at the same time I want to achieve a fully developed flow (actual velocity profile) right at the inlet without having to extend the inlet? Before this, I set the inlet as a velocity-inlet and I used UDF to get actual velocity at the inlet.

I am very grateful if someone could give their opinion on this matter.
Thank you in advance.

LuckyTran · December 15, 2018, 18:10

You can, but not in the way you are thinking. You can't specify static pressure and velocity at the inlet because that would imply the inlet is supersonic. You're trying to do something that violates physics. Don't use a physics based solver if that's what you want to do.

hanis_iz · December 16, 2018, 21:48

Thank you for your opinion. I really appreciate it since I am not sure about it

December 15, 2018, 02:04	Is it possible to have an actual velocity profile at the inlet with pressure-inlet BC	#1
hanis_iz New Member hanis izzati Join Date: Oct 2018 Posts: 6 Rep Power: 8	I am doing research on airflow condition in airways. Is it possible if I set the inlet's boundary condition as pressure-inlet but at the same time I want to achieve a fully developed flow (actual velocity profile) right at the inlet without having to extend the inlet? Before this, I set the inlet as a velocity-inlet and I used UDF to get actual velocity at the inlet. I am very grateful if someone could give their opinion on this matter. Thank you in advance.

December 15, 2018, 18:10		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,752 Rep Power: 66	You can, but not in the way you are thinking. You can't specify static pressure and velocity at the inlet because that would imply the inlet is supersonic. You're trying to do something that violates physics. Don't use a physics based solver if that's what you want to do. Last edited by LuckyTran; December 15, 2018 at 19:31.

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December 16, 2018, 21:48		#3
hanis_iz New Member hanis izzati Join Date: Oct 2018 Posts: 6 Rep Power: 8	Thank you for your opinion. I really appreciate it since I am not sure about it