Introduction
The selective subcycling method in Abaqus/Explicit is based on domain decomposition. In this method subcycling zones are defined that remain unchanged during the analysis. The domain-level parallelization method (Parallel Execution in Abaqus/Explicit) is invoked automatically when subcycling zones are defined. Each subcycling zone, as well as the non-subcycling zone, is independently decomposed into the user-specified number of parallel domains. The “nonsubcycling” domains are defined as the parallel domains that are derived from the non-subcycling zone and are integrated with the largest stable time increment. The remaining parallel domains derived from the subcycling zones are integrated using smaller time increments, or “subcycles.”
The subcycle time increment sizes are chosen as integer divisors of the time increment used in the nonsubcycling parallel domains. Therefore, all parallel domains exactly reach the same time points as the nonsubcycling parallel domains. During subcycling, nodes that lie on the interface with the non-subcycling zone require special treatment. The velocity at the interface nodes is taken from the non-subcycling zone and is constant during subcycles. This produces an interface node displacement field that varies linearly during the subcycles.