INEEL to host international seminar on reactor modeling code

"The purpose of the meeting is to get people who use the code to come together and share ideas on how to implement it, define problems and discuss improvements," said Gary Johnsen, the RELAP5 program manager.

RELAP5-3D is a code developed at the INEEL to create computer models of water-cooled nuclear reactors. The code was designed primarily to simulate accidents in order to evaluate the effectiveness of emergency safety systems. With three-dimensional capabilities recently added, it has been used to improve emergency operating procedures for Russian-designed reactors throughout Eastern Europe, and to enhance the fidelity or accurateness of reactor operator training simulators in the United States.

The original RELAP5 code was developed in 1978. Ongoing improvement and updating--partly an outcome of these annual meetings--have resulted in the current RELAP5-3D program.

This year, the seminar will be in West Yellowstone, Mont. Johnsen said he always tries to hold it near the INEEL to allow a greater number of lab personnel to attend. Visitors will be coming from Europe and Asia, and from across the United States.

At the seminar, users will present papers on innovative ways they have employed the code. Later, the user group's full membership will vote on proposed improvements for the code. Most users of RELAP5-3D are operators and builders of nuclear reactors, for whom the original code was designed, but other industries using water and steam flow systems have found uses for it as well.

The current phase of development for the code is implementing changes needed for modeling the next generation of nuclear reactors, called Generation IV concepts, some of which will use helium, molten lead and other coolants instead of water.

This seminar is open to the public.

The INEEL is a science-based multi-program national laboratory dedicated to support the U.S. Department of Energy's missions in environment, energy, science and national security. The INEEL is operated for the DOE by Bechtel BWXT Idaho, LLC.