Hi Abaqus users,
I'm modelling the impact between two cylindrical objects. The bodies hit each other on their flat surfaces. The problem I'm encountering is that I get some "instabilities" on the contact surface (see attached picture). Some nodes displace considerably, and the analysis aborts a few instants after contact starts, due to excessive elements deformation. I'm using General Contact, with interaction prop defined by hard contact and penalty friction (coeff=0.25). I also have to say that if I model a small curvature on the impact surface of one of the two bodies, the analysis runs smoothly until the end.
Does anyone know why I have this problem and how I can solve it?
For impact mechanics, an explicit solution/solver in any software is preferred. Implicit solvers shall have convergence issues. Explicit solver shall have simple general contact and it shall not have convergence issues..
For geometry of this type, based on contact forces, the bodies can get displaced in any directions and for that kind of large deflection, implicit contact shall have convergence issues..
Venkateswarlu Gattineni, I didn't specify, sorry. I'm already using the explicit solver.
This type of messing cause instability of contact, it's better to partition using a structured mesh will help u.
Dear Alessandro,
did you try to model the contact with a surface-to-surface contact instead of the general one? Furthermore, what kind of element are you using?
Hi Gaetano Pianese
no, I actually didn't. Maybe I can try as well. The elements I'm using are the C3D6. Apparently was an issue related to hourglassing. I solved it by using C3D8R with hourglassing control.
Ok, I suggest trying the surface-to-surface contact first with the C3D8 elements and then with C3D8R. Furthermore, for the latter, try first without hourglassing control, and then with it. Let me know!
- Badges
- Science topic
- Similar topics
- Engineering
- Mechanical Engineering