Each session of simulation is facing unknown world all the time since either the process of unit, certain zones, or plant level is changing or because different malfunctions and failures can happen depending on operations and the behavior interactions among units. In dynamic simulation to change a model, for instance, according to the ongoing status' of the plant's units is very information intensive process. The emphasis is on how to builds model of units with the least interaction of human. This is based on the status of the topology (opened-closed valve), state of a unit (reaction might occur) and the state of the connected units (flow direction in a pipe depends on the pressure difference between connected units). For this purpose the different kinds of changes in a model are identified. Although a novel simulation architecture is proposed, the present paper gives details barely on one part of it, that is, on the model generation activities.