[LuckyTran]

I've had this issue in Fluent v17 & v18. My guess is, it can happen in any version of Fluent. Does anyone know a workaround?

I'm running LES on a pipe flow and want to double the length of my pipe by appending the case-data.

/mesh/translate ## 0 0
/mesh/modify-zones/append-mesh-data " "

Then I start merging zones and surfaces etc. I can merge the cell zones no issue. But there is a huge memory leak when I try to fuse the overlapping boundaries and the interior zones.

/mesh/modify-zones/merge-ones fluid-1 fluid-1.1
this usually works okay. The next two always give me problems.
/mesh/modify-zones/fuse-face-zones wall-1 wall-1.1
/mesh/modify-zones/merge-zones interior interior.1

My mesh is currently only 7 million cells (x2=14 million). It shouldn't need more than 30 GB. However, when I run fuse-face-zones or try to do merge-zones on the interior I get a memory leak and the sim just asks for all the memory that is available >250GB RAM. Usually the fuse-face-zones will work (but uses ~210GB of RAM) and then the merge-zones interior will crash on a cortex error, probably because Fluent ran out of memory. In parallel goes just grabs all the RAM and crashes. In serial, it immediately throws a segmentation fault without hogging the memory.