The Neutral Model Format for Building Simulation

The idea of a completely general simulation environment, where a user can interconnect predefined submodels freely into a tailored system model, is today a reality. In the field of building simulation, existing environments like TRNSYS and HVACSIM+ along with several new developments, allow fully coupled models of envelope, distribution systems and controls at an arbitrary level of detail. However, the ultimate usefulness of any of these tools hinges on the existence of a comprehensive library of component models and the development cost of such a library will easily ex ceed that of the environment itself. In this report a Neutral Model Format (NMF) is specified. NMF models can be automatically translated into the format of a number of environments. Based on NMF, independent libraries can be established, and inter-environment model exchange is likely to increase. Since the first NMF proposal in 1989, several prototype translators have been developed, model libraries have been written, and the concept has earned acceptance among experienced users. This report repeats the mode lling principles underlying NMF and presents a brief reference manual. A formal syntax definition and some model examples are presented in appendices.