To support the functionality of RELAP5-3D for best-estimate reactor simulation code, a variety of utility programs were developed at Idaho National Laboratory. Conversion and upgrades of RELAP5-3D to FORTRAN 95 required the upgrades of these utility programs as well. Pygmalion (Pygi) and the RELAP5-3D Graphical User Interface (RGUI) are two of the utility programs that were upgraded and enhanced.

Pygi creates a copy of a RELAP5-3D input file with updated initial condition information. From the restart/plot file of the RELAP5-3D run of an input deck, Pygi obtains the final conditions for each component. It creates a new input file that replaces the original input file values with updated conditions. This provides an accurate and efficient means of creating new input decks with steady-state input conditions.

RGUI is an alternative to the command line interface for performing RELAP5-3D–related work. RGUI provides single-interface access to other RELAP5-3D tools such as Pygi. It is highly configurable, allowing the user to customize the environment. The interface runs on both Linux and Windows.

This suite of utility programs is continually being enhanced to provide better support for RELAP5-3D users. This technical note provides details of Pygi and RGUI functionality. Future plans for enhancements are also included.