Development of a Benchmark Problem and Implementation of the DRF Methodology for Reactor Dosimetry in the Extended Beltine Region

Abstract

Recent interest in extending the operating life of nuclear power reactor throughout the United States beyond 60 years of operation is prompting innovation in dosimeter response solving methods to aid in understanding material embrittlement of nuclear reactor pressure vessels. This innovation is possible due to improved computational hardware and simulation techniques which allow analysis of 3-D response calculations for geometry beyond what is possible for conventional methods used for lifetime extension of younger reactors. There is a need to create a benchmark problem with a high-fidelity reference solution to act as a point of comparison for the new dosimeter response methods. The Tennessee Valley Authority (TVA) Watts Bar Unit 1 Reactor Pressure Vessel Fluence Benchmark is being developed to fulfill this need. This thesis presents the development of the TVA Watts Bar Unit 1 Reactor Pressure Vessel Fluence Benchmark. Further, the Detector Response Function (DRF) Method is used to solve part of the problem presented in the benchmark. This solution is treated as a test to lay the groundwork for utilizing the DRF method to find a full solution for the TVA Watts Bar Unit 1 Reactor Pressure Vessel Fluence Benchmark problem in the future. Data is extracted throughout the presented methodology and analyzed for physical accuracy. The DRF method is chosen for this work as a method with low computation times, and the results from are compared to a reference calculation. Improving the reaction rate calculation methods will ultimately reduce the computation time required for safety analysis of nuclear power plant lifetime extensions, saving institutions and companies both time and money.