Coupled Wall

qntldoql · October 19, 2021, 10:47

Hello,

Currently I am trying to simulate 3 domain problems.
There are two layers of solids beneath an air channel.
So the problem effectively becomes fluid (air) domain in contact with the primary solid domain, which is in contact with the secondary solid domain.

Instead of creating the entire mesh as its own, I have created and imported the meshes for each domain.
Then I used coupled-wall interface option to link (Primary_bottom) with (Secondary_top), etc.
This creates Intf:01 - wall and its shadow.
However, primary_bottom and secondary_top remains. (as non-overlapping walls)

When I run the simulation, there is a heat transfer (flux) between the Intf:01-wall and its shadow. (for ex. 1101W for intf:01 and -1101W for its shadow) Therefore I believe it is working correctly.

However, no flux is present between primary_bottom and secondary_top "Walls".
In this case, does fluent "ignore" the presence of primary_bottom and secondary_top and only treat "intf:01" and its shadow in place?

Additionally, when I tried to change boundary condition of the priamry_bottom and secondary_top walls to "via system coupling", it does not allow. It defaults to adiabatic wall.
(However, I can observe the temperature difference for the secondary and primary domains, leading me to believe only the interfaces are treated as otherwise they both should remain at the same temperature.)

I apologize for the long wall of text, but I wanted to confirm if what I believe is correct or not.

LuckyTran · October 19, 2021, 13:32

Yeah that's the way it works. The boundaries of the original mesh adopt/inherit the properties of the interface. Basically, the stuff happening in the interface is used as BC's of the original disjoint meshes.

qntldoql · October 19, 2021, 13:53

Thank you! I was worried as to if the original wall were somehow acting as a thin wall very near the interface, acting similar to a barrier.
Now I understand that interface condition is "transferred" to the original wall (after the name change to non-overlapping wall) instead of keeping the "adiabatic" condition of the non-overlapping wall.

October 19, 2021, 10:47	Coupled Wall	#1
qntldoql New Member qntldoql Join Date: Sep 2020 Posts: 15 Rep Power: 6	Hello, Currently I am trying to simulate 3 domain problems. There are two layers of solids beneath an air channel. So the problem effectively becomes fluid (air) domain in contact with the primary solid domain, which is in contact with the secondary solid domain. Instead of creating the entire mesh as its own, I have created and imported the meshes for each domain. Then I used coupled-wall interface option to link (Primary_bottom) with (Secondary_top), etc. This creates Intf:01 - wall and its shadow. However, primary_bottom and secondary_top remains. (as non-overlapping walls) When I run the simulation, there is a heat transfer (flux) between the Intf:01-wall and its shadow. (for ex. 1101W for intf:01 and -1101W for its shadow) Therefore I believe it is working correctly. However, no flux is present between primary_bottom and secondary_top "Walls". In this case, does fluent "ignore" the presence of primary_bottom and secondary_top and only treat "intf:01" and its shadow in place? Additionally, when I tried to change boundary condition of the priamry_bottom and secondary_top walls to "via system coupling", it does not allow. It defaults to adiabatic wall. (However, I can observe the temperature difference for the secondary and primary domains, leading me to believe only the interfaces are treated as otherwise they both should remain at the same temperature.) I apologize for the long wall of text, but I wanted to confirm if what I believe is correct or not. Last edited by qntldoql; October 19, 2021 at 11:52.

October 19, 2021, 13:32		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,751 Rep Power: 66	Yeah that's the way it works. The boundaries of the original mesh adopt/inherit the properties of the interface. Basically, the stuff happening in the interface is used as BC's of the original disjoint meshes. qntldoql likes this.

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October 19, 2021, 13:53		#3
qntldoql New Member qntldoql Join Date: Sep 2020 Posts: 15 Rep Power: 6	Thank you! I was worried as to if the original wall were somehow acting as a thin wall very near the interface, acting similar to a barrier. Now I understand that interface condition is "transferred" to the original wall (after the name change to non-overlapping wall) instead of keeping the "adiabatic" condition of the non-overlapping wall.