I use Abaqus/Standard. Element distortion occurs frequently in my analysis and apparently it doesn't matter how hard I try to change the meshes , at least a few number of elements would be distorted. However, If you create an acceptable meshing , the solution will converge and the job will be completed but with a number of warnings indicating excessive distortion of some elements.
I am really eager to know to what extend may the existence of distorted elements adversely affect the accuracy of the results , specially the displacement field?
The same for negative eigenvalues. This warning seems to happen without any special clue , I think it indicates the possibility of buckling if the load is exerted in the opposite direction, so I think this is not a negative factor to the accuracy of my analysis, is it?
I am very thankful for your insightful replies