[snappyHexMesh] not symmetric mesh around symmetric geometry

Aeronautics El. K. · March 4, 2015, 14:03

Hello all.

I'm trying to mesh an airplane which is obviously symmetrical along the centreline.

I've tried quite a few different things:
a. take the whole aircraft and have blockMesh chop-off the right half of the airplane
b. take the whole aircraft and have blockMesh chop-off the left half of the airplane
c. mesh the whole airplane as it is

I'm running snappyHexMesh in parallel.

In every single case that I've tried, the right and left part of the mesh are not symmetric as one would expect. This is especially surprising in the case of the full aircraft.
The problem is around the trailing edges which get better resolved on one side of the aircraft but not on the other (or either the left-mesh or the right-mesh).
Explicit or implicit feature extract doesn't seem to have any effect.

Does anyone have any idea why this might be happening?

ps
I'm currently running another case with exactly the same case but on one processor to see if that makes any difference.

GrivalszkiP · May 23, 2020, 03:51

Hi!

Have you solved the problem? If yes, how?

March 4, 2015, 14:03	not symmetric mesh around symmetric geometry	#1
Aeronautics El. K. Senior Member Lefteris Join Date: Oct 2011 Location: UK Posts: 341 Rep Power: 16	Hello all. I'm trying to mesh an airplane which is obviously symmetrical along the centreline. I've tried quite a few different things: a. take the whole aircraft and have blockMesh chop-off the right half of the airplane b. take the whole aircraft and have blockMesh chop-off the left half of the airplane c. mesh the whole airplane as it is I'm running snappyHexMesh in parallel. In every single case that I've tried, the right and left part of the mesh are not symmetric as one would expect. This is especially surprising in the case of the full aircraft. The problem is around the trailing edges which get better resolved on one side of the aircraft but not on the other (or either the left-mesh or the right-mesh). Explicit or implicit feature extract doesn't seem to have any effect. Does anyone have any idea why this might be happening? ps I'm currently running another case with exactly the same case but on one processor to see if that makes any difference. __________________ Lefteris

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May 23, 2020, 03:51		#2
GrivalszkiP Member Grivalszki Péter Join Date: Mar 2019 Location: Budapest, Hungary Posts: 39 Rep Power: 7	Hi! Have you solved the problem? If yes, how?