[daylen]

Hi, im learning the cooling sphere tutorial using chtMultiRegionFoam, the Allmesh contains the following line:


runApplication splitMeshRegions -cellZones -defaultRegionName fluid -overwrite


I don´t understand the above line, what is -defaultRegionName and fluid?

[GerhardHolzinger]

Originally Posted by ifrit54

Hi, im learning the cooling sphere tutorial using chtMultiRegionFoam, the Allmesh contains the following line:


runApplication splitMeshRegions -cellZones -defaultRegionName fluid -overwrite


I don´t understand the above line, what is -defaultRegionName and fluid?

Imagine building a CHT-case from the base mesh shown in the attached image. The base mesh is a simple cylinder which represents the fluid region within a pipe.
Now you extrude the cylinder walls to create a layer of cells which represents the pipe's wall.
Finally, you run splitMeshRegion to separate the two domains.


Why the need for a default region name?

extrudeMesh automatically creates a set (or zone) called addedCells, which represents the pipe's wall. The remaining cells of the fluid region, i.e. the cells of the base mesh you started with, aren't part of any set or zone. So, splitMeshRegion will name the newly created mesh region, created from cells that are part of no set or zone, simply region0.

In such a case, you can use the command line argument defaultRegionName to provide a more telling name.
That's all

[daylen]

thank you for your reply now i understand