A new set of simulation tools, developed to support the overall preparation process of full-scope simulators for nuclear reactors, is introduced. Using a uniform user interface and standardized software development platform, the tools are grouped around a framework called SIMTONIA. Here we give a brief description of the framework and its elements, outlining the most important features of the system. The vitality of the framework is demonstrated by a simple modeling exercise.

In this paper we present three different nuclear industrial applications of the SIMTONIA framework developed by CER. First, we demonstrate how we could utilize SIMTONIA's sequential engine for the verification and validation of the new control rod and reactor power controller system of Paks NPP. In our second example, the application of SIMTONIA's visual engine for system monitoring in the VERONA core monitoring system of Paks NPP will be presented. Finaly, the critical safety monitoring system and electronic operational rules of the plant computer of Paks NPP will be briefly introduced focusing on the application of SIMTONIA's sequential engine as an evaluation tool of logic diagrams.