u/Extreme-Committee689

HELP simulation not converging
▲ 4 r/STAR_CCM+1 crossposts

HELP simulation not converging

https://preview.redd.it/9t230u8jq91h1.png?width=1012&format=png&auto=webp&s=8dc659ca0c48c29c9d97a87aab6361fef5782c89

https://preview.redd.it/3zmmioalq91h1.png?width=1287&format=png&auto=webp&s=6faab53ed71238bd53bafede8978612908679c9c

https://preview.redd.it/gjm25s2nq91h1.png?width=997&format=png&auto=webp&s=9c3b58bfbca0b8fb99316d52b674b6dcc67699b9

Hi everyone,
I’m working on a CFD simulation of flow inside a pipe containing a TPMS structure. I think the mesh is reasonably good: mesh diagnostics do not show major issues, and I only have around 50 problematic cells out of ~8 million total cells. Considering the complexity of the geometry, I assume that should be acceptable.

Right now I’m trying to first solve the case using the k-epsilon model to reach convergence, because with k-omega the residuals remain high and do not decrease properly.

Am I approaching this the wrong way? What should I check next?
Could the issue be related to boundary conditions, near-wall treatment, mesh quality in critical regions, relaxation factors, or something else?

Any advice or suggestions would be really appreciated.

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u/Extreme-Committee689 — 8 days ago

https://preview.redd.it/deyajosdsywg1.png?width=476&format=png&auto=webp&s=7681121c2576b85a9d9a9c0cac26673b56e8ee59

hi everyone how would u create this kind of mesh in STAR CCM+? i've tried extrudind the surface and using a directed mesh with custom control for the square inside but it doesn't work, i've also tried drawing the sketch on the face extruding it and then doing the directed mesh but also doesn't work. Do u have some hints?

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u/Extreme-Committee689 — 30 days ago