Sheet Metal Forming Simulation with IGA in LS-DYNA ®

In the last few years, numerous research work has been devoted to Isogeometric Analysis (IGA). IGA is a finite element technology in which computer-aided design (CAD) geometric description is invoked to perform numerical analysis. The most widely used mathematical description in CAD is non-uniform rational B-splines (NURBS) and therefore NURBS-based shell and solid finite elements have been implemented into LS-DYNA. This paper describes the recent advances of the NURBS-based shell implementation in LS-DYNA to enable the IGA technology for the use in sheet metal forming applications. Necessary features like stress, strain, thickness, and history variable mapping from one stage to the other, the trimming of the formed part and other typical features used by the forming analysts have been enabled for the use with NURBS-shells. The new keywords will be explained and the multistage forming process will be analyzed by means of an example. A comparison with current state-of-the art methods is provided and further developments are outlined.