PITTSBURGH – Oct. 20, 2017 – Westinghouse Electric Company today announced that it has received approval from the U.S. Nuclear Regulatory Commission (NRC) for two new important analysis methodologies that will be used to upgrade Westinghouse- and Combustion Engineering-based nuclear steam supply system (NSSS) safety analyses.
The approvals granted are for the new FULL SPECTRUM™ Loss of Coolant Accident (FSLOCA™) methodology and the Performance Analysis and Design Model software code update, PAD5. FSLOCA is capable of improved modeling of the transient response in a pressurized water reactor to the full spectrum of LOCA break sizes that could occur, and PAD5 is the next generation of the Westinghouse fuel rod design performance code.
“These codes were developed to work in concert with each other to maximize analytical margin for nuclear utilities,” said Michele DeWitt, senior vice president, Nuclear Fuel. “FSLOCA and PAD5 offer the very latest in analysis data and statistical methods, while also meeting current regulatory expectations.”
PAD5 enables utilities to fully address thermal conductivity degradation with new modeling and other updates. It represents a significant step forward in accurately modeling nuclear fuel performance phenomena.
The FSLOCA methodology is an innovative product that has been in development for more than 10 years. It is the first NRC-approved method in the industry for best-estimate analysis of small-break LOCAs. Application of the FSLOCA methodology will provide improved plant operational flexibility while continuing to meet all applicable LOCA analysis acceptance criteria.