Development and Analysis of TREAT Neutronics Benchmarks

The Transient Reactor Test Facility (TREAT) was designed in the late 1950s to test nuclear fuels and materials under extreme conditions and has been recently restarted by the U.S. Department of Energy to provide the transient test capability to evaluate the performance of innovative nuclear fuels under accident conditions. Benchmark experiment data are required to support the operation of TREAT and to validate the computational analyses necessary to design and evaluate the experiments. Therefore, in this paper, benchmark problems based on the minimum critical (MC) core and M8 Power Calibration Experiment (M8CAL) core of TREAT were developed and analyzed using the Monte Carlo code Serpent. The eigenvalue, temperature coefficient, and flux distributions for both the MC core and the M8CAL cores were calculated and compared to the experimental data. All the calculated values compared well to the experimental data, and both problems were subsequently approved as International Reactor Physics Experiment Evaluation Project benchmarks.