convergence problem higher outlet pressure than inlet

Martin_Sz · August 27, 2021, 00:49

Hello
How correct setup boundary conditions:
My Case
I have two inlets - one 10 bar pressure , second 1.5 bar absolute pressure
outlet - 2 bar absolute pressure.
And thats is a problem that pressure over outlet is better than on inlet 2.
And If I run steady state (ideal gas) My imbalances are high.
My bc's
Inlet1 - velocity inlet
Inlet 2 - pressure inlet with total pressure
Outlet - pressure outlet

ghorrocks · August 27, 2021, 05:43

Are you doing this in CFX or Fluent?

If CFX then please attach your output file.

Martin_Sz · August 29, 2021, 04:45

Yes Im doin in CFX
Convergence problem is that I have reverse flow on outlet and all gas is goin to inlet 2 .

ghorrocks · August 29, 2021, 05:34

As I said previously - If CFX then please attach your output file.

Also please attach an image showing the problem flow.

August 27, 2021, 00:49	convergence problem higher outlet pressure than inlet	#1
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 232 Rep Power: 12	Hello How correct setup boundary conditions: My Case I have two inlets - one 10 bar pressure , second 1.5 bar absolute pressure outlet - 2 bar absolute pressure. And thats is a problem that pressure over outlet is better than on inlet 2. And If I run steady state (ideal gas) My imbalances are high. My bc's Inlet1 - velocity inlet Inlet 2 - pressure inlet with total pressure Outlet - pressure outlet __________________ Quick Tips and Tricks, Tutorials FLuent/ CFX (CFD) https://howtooansys.blogspot.com/

August 27, 2021, 05:43		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	Are you doing this in CFX or Fluent? If CFX then please attach your output file. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

August 29, 2021, 04:45		#3
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 232 Rep Power: 12	Yes Im doin in CFX Convergence problem is that I have reverse flow on outlet and all gas is goin to inlet 2 . __________________ Quick Tips and Tricks, Tutorials FLuent/ CFX (CFD) https://howtooansys.blogspot.com/

August 29, 2021, 05:34		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	As I said previously - If CFX then please attach your output file. Also please attach an image showing the problem flow. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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