Learning Forum

[meldeeb]

I want to use rough contact between belt and pulley to simulate timing belt instead of modeling the teeth of it.

[Chris Quan]

Rough contact is not available in Explicit Dynamics system and LS-DYNA system.
In Explicit Dynamics system, you can use either Frictional Contacts with high coefficient of friction or bonded contacts with breakable in tension to represent the rough contacts approximately.
In the frictional contacts with high coefficient of friction, high frictional force will limit the sliding motion between the belt and the pulley.
In the bonded contacts with breakable in tension, bonded contacts prevent the sliding motion between the belt and the pulley. You can pick the maximum tensile value strategically to break the bonds when the belt and the pulley start to separate.

[meldeeb]

Thank you Ms. CXQUAN,
I have another question, for application like that, should I do explicit dynamics analysis or transient analysis?
Knowing that, I am simulating a full robot and I am caring about deformation at some parts??
I transient analysis is better, in this case, the idea of rough contact is good or not?

[Chris Quan]

If the event duration in your simulation is long, such as in seconds, you may consider to use Transient Structural Analysis since you can use larger time step to reduce the running time.
If the event duration in your simulation is short such as in milli-seconds and material behavior is highly nonlinear, you may consider to use Explicit Dynamics Analysis, since it avoids frequent matrix formation and inversion and thus runs more efficiently.
For the cases between, you need to carefully examine the problem and then make a decision. If you expect that the maximum stress from the simulation is few times higher than the initial yield stress, I would suggest using Explicit Dynamics Analysis. If the expected maximum stress is elastic or a little bit above initial yield stress, I would suggest using Transient Structural Analysis.