OPTIMIZATION OF THE ECONOMICS OF FISSILE MATERIAL AT THE FIRST CRITICALITY OF A 10 MWT PEBBLE BED REACTOR

• Main Author: Amisha Daniel Rahmany, Kharisma
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/83941
• Institution: Institut Teknologi Bandung

Currently, the human need for electricity continues to grow every year. Nuclear energy as a clean and reliable energy can be an alternative energy. Reflecting on past problems and adjusting to human needs, a generation IV nuclear reactor was developed.The High Temperature Gas-cooled Reactor (HTGR) as part of generation IV is a gas-cooled reactor that has good performance and has the potential to be applied to many aspects. By using textitpebble bed as fuel, a better safety system and refueling capability are obtained when the reactor is active. This research focuses on optimizing the fuel economy of the 10 MWt Pebble Bed Reactor under the first criticality condition. Using openMC, two types of models were generated, simplified model and high fidelity model. Neutronic aspects were analyzed by considering the influence of the number of neutrons initiated, the height of the pebble bed in the reactor core, the ratio of fuel and dummy, and enrichment in the range of 14% to 20%. Based on the results of benchmarking, the simplified model gives a value of ke f f of 1.0120±0.00021 while the high fidelity model gives a value of 1.03207±0.00021. Then, the setting of 300,000 initiated neutron particles is able to provide good count confidence with a standard deviation of 8×10?5 . Furthermore, considering the mass of U235, the configuration that requires the least amount of fissile material is obtained at a height of 180 cm with a fuel:dummy pebble ratio of 26:74 and a U235 enrichment of 18%. when considering the cost of enrichment, a height of 180 cm with a ratio of 36:64 and an enrichment of 14% can be another option.