Hi,
Whenever you have a diverging simulation, it’s always a good idea to go through the steps in this article. The troubleshooting steps are always the same for every single project.
In any case, if we check the mesh quality (troubleshooting step number 3 in the article), we have some very bad elements in the domain:
As you pointed out, the divergence was below the tire. It turns out that we have a gap that closes asymptotically between the tire and the bounding box of the enclosure:
This is an issue, because the gap gets smaller and smaller, which results in the boundary layers breaking, very tiny cells being generated, which ultimately causes the mesh quality to be very poor. To solve this, you can either:
- Have the enclosure intersect with the tire (i.e. make the enclosure shorter), so the small gap is gone
- Use some small pads for the tires, which is a quite common approach. Again, the idea is to prevent these asymptotic gaps from being generated.
Cheers