Abstract (EN):
Reliable numerical analysis of sheet metal forming processes using commercial finite element programs involves a variety of fields within computational mechanics area. Material models, contact algorithms, robust and fast incremental and iterative solution techniques are among the key factors that a finite element package must rely upon. Nevertheless, the finite element formulation itself still represents a milestone of crucial importance in the overall quality of the final solution. As sheet metal forming processes present very strong test cases to the performance of finite elements, robust formulations are then desired. In this work, classes of finite elements involving only the Enhanced Assumed Strain (EAS) method are analyzed. Starting from an innovative approach to eliminate transverse shear locking in shell elements (S4E6P5 shell element) and going through a new approach for a volumetric and transverse shear locking-free solid-shell element with a low number of internal variables (HCiS12 solid-shell element), the authors adopt formulations entirely based on the EAS approach with full integration. This methodology proved to be reliable and also free of instabilities arising in other formulations with grounds on mixed approaches. Validation analyses involving anisotropic sheet metal forming processes are shown, with the overall performance of both elements and formulation is verified.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
6