ISLAND: Interactive solution language for an adaptive NIKE driver. User Manual.

摘要

Effective solution strategies to solve the global nonlinear equations are a vital part of an implicit nonlinear finite element analysis code such as NIKE2D. Efficient strategies make good use of computational resources, and allow larger and more complex analysis models to be studied. Robust algorithms are essential to handle the complex nonlinearities which arise in many engineering applications, such as metalforming process simulation. Our research indicates that robustness can be best achieved through adaptive solution strategies. This adaptivity and flexibility has recently been incorporated into NIKE2D. Temporal and algorithmic adaptivity is achieved through the development of ISLAND (Interactive Solution Language for an Adaptive Nike Driver). This report serves as a User Manual for the ISLAND language and its application to the definition of adaptive solution strategies in NIKE2D. ISLAND substantially improves the robustness of NIKE2D when solving strongly nonlinear problems. In addition, ISLAND allows new classes of constrained problems to be solved which could not previously be studied. Applications span many process simulation problems, including superplastic forming. These new solution control features make NIKE2D a ''smart code,'' and permit many new and challenging problems to be addressed.