Erik Kostson
Ansys Employee

 

Hi

 

These are stress singularities.

 

See here for a good article on this topic.

https://www.linkedin.com/pulse/stress-singularities-concentrations-mesh-fea-marcos-ac%C3%ADn-gonz%C3%A1lez

 

For frame type of structures like the one you show, one would use often beam elements not solid 3D parts/elements (beams do not suffer from the above like solid 3D elements do):

See here for a tutorial.

 

Thank you

 

Erik