VERA Software Validation using In-Plant Data

As nuclear plant owners extend their operating licenses from 40 to 60 or 80 years, there is uncertainty about the long-term health of major plant components subject to high doses of radiation including the reactor pressure vessel, core internals, and concrete bioshield. Currently, nuclear power plants cannot accurately predict when a reactor component has reached the end of its useful life or when and why a process anomaly will occur due to lack of appropriate modeling and simulation software. The Virtual Environment for Reactor Analysis software, developed by the Consortium for Advanced Simulation of Lightwater Reactors can fill this gap, but requires additional validation to be commercially viable for ex-core neutron fluence and advanced troubleshooting applications. To enable the Virtual Environment for Reactor Analysis software to be used as an aging management and advanced troubleshooting tool, a research and development effort is proposed that leverages data from over 40 years of in-plant testing to validate key aspects of the software. This validation methodology will enable the Virtual Environment for Reactor Analysis software to be integrated into plant aging management programs where it can be used for advanced thermal hydraulic troubleshooting and prognostics informed by ex-core neutron fluence data. These new services will allow plants to expedite troubleshooting, save time and money, and gain additional insight into the aging and health of reactor internals. This work will result in the ability to use in-plant data as an input to the Virtual Environment for Reactor Analysis software, augmenting current troubleshooting approaches. The research and development effort proposed herein will create a method for validation and integration of the Virtual Environment for Reactor Analysis software in nuclear power plant aging management and troubleshooting programs. During the project, cross correlation and signal coherence will be used in conjunction with in-plant data to determine what process parameters are highly correlated. Regression techniques will be used to develop empirical relationships between process parameters and ex-core neutron flux and in-core thermal hydraulics. These datasets and relationships will then be used to demonstrate the ability to validate the Virtual Environment for Reactor Analysis software. These demonstrations will be the basis of a commercial validation and advanced troubleshooting methodology to be developed in Phase II. The proposed services will increase the profitability of commercial nuclear reactors by reducing operation and maintenance costs and mitigating unplanned maintenance outages. The United States will maintain its position as a leader in the nuclear industry and benefit from continued clean energy generation from nuclear power. This research can serve the advanced reactor community and spur innovation and deployment of next generation reactors.