[Karunakar Reddy]

I am trying to simulate heat transfer through ground loop for geothermal heat pump. The outer diameter of the pipe 0.1m and thickness of the wall is 0.02m. The soil domain is of diameter of 1m. The length of the pipe is 30m. I have two interfaces 1. between soil and pipe 2. between pipe and fluid.

I am facing problem with defining coupled heat transfer BC due to formation of empty walls and their shadows at interfaces. I am getting coupled option for these empty walls and their shadows, but not for the interface walls i have given in named selection (without formation of any shadow walls for these). Also few other empty walls are being created. How can i define these walls because because they are not being displayed. Is it sufficient to give coupled BC on either soil or fluid side of pipe with wall thickness. Or Do i have to define it at both interface walls. If so how can i deal with these empty walls ? I am attaching my geometry and mesh files.Please help me.

[vasava]

If I understood correctly, you have named the walls that are part of the interfaces. This is not correct. If the walls are part of an interface you need not name them.

Generation of extra walls merely indicate that them meshes on source and target walls are not matching.

Also in fluent you can remake the interfaces and while doing so select 'matching' and 'coupled wall'. This should be enough to have conjugate heat transfer between walls.

[Karunakar Reddy]

Thank you sir, it seems working.