Error Message in CFX12

SUNSHINE · November 2, 2009, 06:58

Hi all,

when running simulaiton there is an error message appear as

A wall has been placed at portion(s) of an OUTLET |
| boundary condition (at 100.0% of the faces, 100.0% of the area) |
| to prevent fluid from flowing into the domain. |
| The boundary condition name is: Outlet. |
| The fluid name is: Fluid. |
| If this situation persists, consider switching |
| to an Opening type boundary condition instead.

I have tried change the outlet type to Opening type and the error message still appear. Anyone know the reasons?

Also,

When i running my simulation with CFX V12 workbench when i do changes on Design moduler, and i update my mesh file. And i re-run again it will give me error msg as above as well.
Possible to tell me what should i do if i make changes on DESIGN moduler what should i do next?

Thank you

uorinopuot · November 4, 2009, 20:32

Hello,
I do not think you need to do anything in the design modeller. This happens because there is fluid going in both directions through your boundary (like a pulsatile flow). Normally in these cases the message is there in the beginning and when the flow becomes faster it disappears. Try to let the simulation to finish. If the message does not disappear at some point try to increase the velocity of the flow to see if it still comes out.

Another idea would be to put inflation layers when you do the meshing, although i do not expect this to make a big difference.

Good luck!

ghorrocks · November 4, 2009, 20:35

It is a warning, not an error. It simply says you have backflow at a outlet and this is not allowed. If the outlet should not have backflow you need to fix it and stop the backflow. If it has backflow you can go to an opening - this allows backflow so I have no idea why it did not work for you.

November 2, 2009, 06:58	Error Message in CFX12	#1
SUNSHINE New Member SUNSHINE Join Date: Aug 2009 Posts: 5 Rep Power: 17	Hi all, when running simulaiton there is an error message appear as A wall has been placed at portion(s) of an OUTLET \| \| boundary condition (at 100.0% of the faces, 100.0% of the area) \| \| to prevent fluid from flowing into the domain. \| \| The boundary condition name is: Outlet. \| \| The fluid name is: Fluid. \| \| If this situation persists, consider switching \| \| to an Opening type boundary condition instead. I have tried change the outlet type to Opening type and the error message still appear. Anyone know the reasons? Also, When i running my simulation with CFX V12 workbench when i do changes on Design moduler, and i update my mesh file. And i re-run again it will give me error msg as above as well. Possible to tell me what should i do if i make changes on DESIGN moduler what should i do next? Thank you

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
CFX12 crashes if trying to open a *.def File	peterputer1	CFX	10	July 28, 2010 08:43
cfx12 x64 meshing: pc has 4 core but only 1 core working for the mesh? why?	leeruoyun	CFX	2	March 23, 2010 13:37
CFX12 rif errors	romance	CFX	4	October 26, 2009 14:41

November 4, 2009, 20:32		#2
uorinopuot New Member Join Date: Oct 2009 Posts: 13 Rep Power: 17	Hello, I do not think you need to do anything in the design modeller. This happens because there is fluid going in both directions through your boundary (like a pulsatile flow). Normally in these cases the message is there in the beginning and when the flow becomes faster it disappears. Try to let the simulation to finish. If the message does not disappear at some point try to increase the velocity of the flow to see if it still comes out. Another idea would be to put inflation layers when you do the meshing, although i do not expect this to make a big difference. Good luck!

November 4, 2009, 20:35		#3
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	It is a warning, not an error. It simply says you have backflow at a outlet and this is not allowed. If the outlet should not have backflow you need to fix it and stop the backflow. If it has backflow you can go to an opening - this allows backflow so I have no idea why it did not work for you.