A simulation environment for multimodeling

Large-scale systems are typically quite difficult to model. Hierarchical decomposition has proven to be one successful method in managing model complexity, by refining model components into models of the same type as the lumped model. Many systems, however, cannot be modeled using this approach since each abstraction level is best defined using a different modeling technique. We present amultimodel approach which overcomes this limitation, and we illustrate the technique using a fairly simple scenario: boiling water. State and phase trajectories are presented along with an implementation using theSimPack simulation toolkit. Multimodeling has provided us with a mechanism for building models that are capable of producing answers over a wide range of fidelity.