Unable to mesh the geometry


#1

Im unable to mesh my geometry which is a SAE Baja chassis.I have designed the geometry in Soldiworks and tried importing a step version of it as well as directly importing the solidworks file, both ending up in the same error as " “NETGEN_2D_2” failed on FACE #1034. Error: Algorithm failed. NgException at Surface meshing: Problem in Surface mesh generation


#2

Hi @gkhatavkar!

I assume that the thickness of the structure leads to the mesh generation error meaning that the structure is too thin to be meshed. I would suggest not to work with the layered structure but use solids for your model, that might work.

@PowerUsers_FEA, any input from your side?

All the best!

Jousef


#3

The geometry has solid tubes of wall thickness 1mm…is it not possible to mesh that kind of geometry ?


#4

Hi @gkhatavkar!

What I can imagine is using the parametric tet-dominant option and make sure you put in 2-3 elements into the thin structure to make it work. Also using first order elements for this kind of simulation seems not to be a good idea because of shear locking - second order elements are the way to go here. I can try it and will also tag @rszoeke here to make sure I am not ignoring something.

All the best!

Jousef


#5

HI @gkhatavkar,
sure generally meshing thin/hollow structures is not impossible, but especially in frame designs like yours there often occur problems at the junctions when multiple tubes are merged. This often leads to geometry artifacts if the merged solids are not modeled very accurately. In your case I can also spot some areas where the fusion of solids seems incorrect:

Maybe you can go back to your CAD tool and search for small/sliver faces that could be removed or self-intersections and have a close look at the junctions of they are merged correctly.
After this has been cleaned up, there should not be any reason why the model shouldn’t mesh - the thin structure of it will just create a very large mesh.

Best,
Richard


#7

Thanks a lot for clarifying @rszoeke!


#8

I corrected my geometry. Removed all intersections, still im getting an error.

.The part used to mesh fine when i had separate tube solids but that cant be used properly hence I combined the tubes in Solidworks after which im getting an error like this one.


#9

Hi @gkhatavkar!

I can still see some artifacts at the junctions, maybe I am mistaken.

Is there a way you can fix this? What I would have started with is a geometry without two layered braces. If the simplified model works we can jump to the next iteration of the design process. What do you think @gkhatavkar?

All the best!

Jousef