When this message is shown, is it possible understand the place in the model
where there is this singularities?
Or all the model is compromise?
If a singularity exists in a zone of the model, I believe that the entire model is compromised. You should post a picture of the zone that Simulate is showing you when that windows appear, so maybe we can help you better since there are many types of singularities. Often, those singularities can be fixed if you add rounds, the most common ¨errors¨ are 90-degree corners in areas with high stress. The system cannot solve what happens there and that window may appear, of course, the entire stress analysis is totally wrong. Check this image.
So If I add rounds, the simulation run better?
I noticed that rounds with small radius return warnings
and the generation mesh process is very slow,
similar behaviour also for the force analises
How small are these rounds? I've used rounds down to 0.3 or even 0.2 mm and I don't believe I've seen warnings about these - and they mesh better than sharp edges.
It should help. There are other singularities as well, like point constraints, point forces...
You can even exclude such singularities from the analysis using an AutoGEM control, Isolate for Exclusion (IEAC), by clicking that AutoGEM control and then selecting the model, and then clicking Preselect Singularities, basically the system will search for singularities on your model and will exclude them from the analysis, that´s the easiest way to avoid singularities, but be careful that the analysis may be wrong or even fail. For this option, you must manipulate also the analysis definition window, search for exclude elements and mark that checkbox.