Needs of object-oriented languages for physics knowledge representation in the simulation field

To cope with the growing demands for simulation models of ever increasing complex industrial systems, the research community effort has been mainly focused on creating different software tools which simplify the modelling task. There is a recognised necessity of modelling tools supporting libraries of non-causal models which could be coupled in the same way as physical units are assembled in a system. This work presents an object-oriented modelling language, PML, designed to support a modelling methodology where system models are described by linking system component models analogously as the system components are linked. This modelling language introduces a new modularization of physical knowledge, making a clear separation between the physical behaviour representation (declarative knowledge) and the computational aspects of model simulation (procedural knowledge).