[zhaozhenkai]

Hi, guys,

i am doing a validation on two ellipses connected by a spring with prescribed motion.

I have used displacementSBRStress motion solver to solve that motion. However, something strange happened. When the structure moves to some point, The running process suddenly blow up with no apparent mistake.

I have checked the mesh quality, At the final step, it was like below:



Checking geometry...
Overall domain bounding box (-2 -2 0) (2 2 0.1)
Mesh has 2 geometric (non-empty/wedge) directions (1 1 0)
Mesh has 2 solution (non-empty) directions (1 1 0)
All edges aligned with or perpendicular to non-empty directions.
Boundary openness (2.398513805e-20 -4.756716453e-20 -5.284828887e-16) OK.
Max cell openness = 2.186121641e-16 OK.
Max aspect ratio = 4.022298722 OK.
Minimum face area = 1.081512183e-08. Maximum face area = 0.007040362657. Face area magnitudes OK.
Min volume = 1.081512183e-09. Max volume = 0.0001002957823. Total volume = 1.599918303. Cell volumes OK.
Mesh non-orthogonality Max: 56.26661203 average: 16.10019355
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 0.5278265916 OK.
Coupled point location match (average 0) OK.

Mesh OK.


there is also no rising residuals or force fluctuation. I have also attached the mesh formation for the final step.

I doubt the problem is about the mesh quality, So I just decreased the prescribed rotational angle and it can run with no problem.
But I cannot understand why for the large rotational angle, there is a mesh quality problem. Does it mean the checkMesh function is not enough to check out all the mesh problem or there are other problems existed in my case that i have not found?

Or can you guys recommend some motion solvers that can deal with large mesh deformation, especially with large body rotation?

PS: I have attached the initial conditions as well. If you need other information, please tell me.

Thanks a lot for any help provided.

ZHENKAI