Meshing howto for CFD.
"Fish in aspic ..."
In case someone is trying to create a mesh for CFD or such from FC here are some experiences of a hard fight over the last 5 days.
1) Don't use "Ruled Surfaces". Use "Loft" instead. Reason: They are exported differently for example into a ".step" file. The former will not be recognized as a volume by meshing tools. The latter will.<br/>
2) Get your geometry right ! Can't be emphazised enough. I had 4 mistakes where lines did not match the endpoints. Debugging this is not really easy <cough> . So do it right from the beginning. The time spend here will pay off in the end.
In case you need to mass convert over 500 surfaces (as i had to do) these python lines worked for me:
Code: Select all
# get Ruled Surface
for i in obj:
if "Ruled_Surface" in i.Name:
print i.Name + " " + i.Curve1.Name + " " + i.Curve2.Name + "\n"
# Get Child Lines/Splines
# Create Loft
ttt.Sections=[App.getDocument("VIIC_Rumpf_Surf2Loft").getObject(c1.Name) , App.getDocument("VIIC_Rumpf_Surf2Loft").getObject(c2.Name)]
And some observations where FC got in the way real hard:
a) Why can i select vertices from the drawing sheet when doing ruled surfaces but doing lofts i have to scroll through an endless list ?
b) Why can i select a "group" within the Draft WB but not in the Part WB for example ?
Debugging the "fish" in gmsh i.e. checking if you get a proper volume. The outer box is a flow channel for example and the inner "hole" is the sub. The whole mesh can then go into OpenFoam.