thanks a lot I will look into it. This is definitely a really really aggrevating problem. The package for the CFD looks so promising but something as important as skin friction is just ruined by these cells and its annoying the hell out of me. Especially because of the interaction of skin friction and flow seperation I can no longer trust the results I got for my detached flow regime

Im sure my pressure should still be correct but what about my drag coefficient? How much do these artefacts effect it???

Correct, physically incorrect results. To be totally honest geometry conformity and these non allign cells slowed down my project tremendously.

"Diamond" boundary faces are unavoidable when background mesh does not align with the boundary surfaces. To get rid of them you need to create a body fitting background mesh.

I think the reason for non-uniform wall shear stress is the non-uniform thickness of boundary layer cells. Did you try to create boundary layers?

If you use layers won't this resolve the issue?

Not necessarily - I got the same thing here with layers: https://discord.com/channels/397772779870486529/796072568385568808/1177814256268361809

I've found that the new castellated fitting or whatever it's called in the recent snappy update helps a lot for this btw

Yes I was trying to mesh with it ^ still have to resolve this further as I get some internal faces... Likely gaps (but detecting gaps etc doesnt resolve it, can be anything to stl etc, so have to further invest some time into it).

Buffer layer what I was telling you about

I wonder if it would help to simply push those terrace tris further away from the boundary by increasing layer thickness..

Certainly wouldn't hurt

Good thing snappy is great at making thick inflation with lots of layers

Oh wait

smoothMesh. Disclaimer: I haven't tried, I'm now busy improving the layer thickness control in it, which is a nightmare to design for parallel processing

Yes this is my exact issue, I've been googling and googline and using LLM's but couldnt find anyone with the a similar issue. Did you ever find any good solution for this or did you just simply live with it?

The 'buffer layers before snapping'

Doesn't fully solve it, but makes it a lot better

And I'm guessing this is for SHM, I dont wanna go back but I guess I have to

cfmesh has been too good to me with the speed and quality of BL

But thank you so much, otherwise this issue might have thrown out my possibility to do CFD of stall angles of an aircraft, because if the wall shear isnt right whos to say the seperation point is correct or the entire flow field around it

Yep

2D or 3D?

3d, blended wing body meaning the surface curves in two directions

great for aerodynamics, horrible for meshing apparently

The state of free meshing is a little dire, unfortunately

guess I'll design aircraft in the future with opensource meshers in mind 🙃

I'm gonna have a look at it right now, I wanted to try out BARAM anyway just becuase I'm a caveman and need GUI's Will write it down in a thread my experience

First I'm gonna test if BARAM even works with this, BARAM is a GUI for openFOAM that uses a modified openFOAM code