No Buildings in Wind Tunnel after SnappyHex mesh

Hi, currently have no access to Windows to load up the GH file.

The input is in the blockMesh component. It assigns a cell size to your background mesh.

Kind regards,
Theodore.

There’s only cell Count.

blockmesh

Unfortunately I can’t check it myself right now, will do in a couple of hours. But if that’s the case this might be a bug. Can you try checking the text info of the input? Also, try setting it to (length_of_wind_tunnel) / 1000 (will give you your 1000 cells, even though it should only work like that if it was cellSize).

P.S.: 1000 cells is REALLY a lot, unless you have a supercomputer around.

Thanks a lot for your responses @TheodorosGalanos,
I will try what you mentioned. I remember that cell size used to be one of the inputs on this component. I am using the latest version from Github and it is no more there.

Yes it was changed to cellCount a while back, although I think we might end up having both inputs. It’s not hard to navigate from one to the other (simply divide the length of your x, y, z with the size you need) but it might be easier to have the input that overrides (perhaps) the other.

I do not intend to have 1000 cells. I am using gradient mesh. You must have observed something either in my response or in the images that I posted that makes you think that. Can you please let me know what that was? May be that is where I am making a mistake.

From your initial post:

When I increase the cell count to {100, 100, 1000} I see the wind tunnel meshed as it should have been, but the buildings are not there.

I also looked into the the max global cells. The number I have set is already quite high. It is 500000000.

That cell count would mean 100 cells on x, y and 1000 on z. Apart from that being a lot, it would also mean more cells on the z which is not usual. Also, the max global cells number you set is 500 million. That’s a lot.

That said, your mesh images don’t show that which might be related to (perhaps) a bug in BF translating the number of cells to actual cell size. I’m hesitant to call this a bug since I still can’t have access to Windows to check.

Thanks @TheodorosGalanos,
I reduced the maxGlobal cells. Now I have 10,00,000 cells
2. I changed cell count numbers.
I could see the buildings when I open the .foam file in Paraview. The cells on the buildings are colored red. What do they mean can you tell?
Attached are some images on running solution. Can you tell is if is going in the right direction? I usually look the the legend of the recolor mesh component and see the velocities. If the velocities are unusually high I stop the solution. In this case, for some reason the legend for the re-color mesh component is not being shown. But we have vectors turned on.


plot

I would really not trust anything shown there for the first 50-100 iterations. It’s not very uncommon to have 50-100 m/s (and even more) in the first iterations. After around 100 iterations it should have stabilized to the region you expect.

Also, for a mesh of this size I would expect things will run much much faster if you disable all these real-time stuff. You can try enabling a bit later to check.

Kind regards,
Theodore.

The solution did not run successfully. I let it run till 2500 iterations. The load probe values component did not produce values for all the probes. Can somebody please take a look at the file I attached?

@TheodorosGalanos,
The model for the high-res UTCI maps. I was wondering if you were able to run it locally with non-orthogonality of less than 60. I am trying to do a similar kind of study and I have started to realize the limitation of the machine.

@TheodorosGalanos,
Following are images of the mesh and cell numbers.

maxGlobalCells = 50,00,000
background cells = 10,00,000
snapped Cells = 71,56,437
non-orthogonality max = 86.27
non-orthogonality avg = 5.69


I am not sure how to bring non-orthogonality under 60.

On-going solution



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