Research Information System
Thesis Type: Doctorate
Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2012
Thesis Language: Turkish
Student: Özgür Erol
Supervisor: HACI MEHMET ŞAHİN
Abstract:Nuclear energy is one of the clean and sustainable energy sources of the world, whose energy need increases every day. Especially the utilization of different types of nuclear fuels increases the reputation of the IVth Generation nuclear reactors in the future. In this study the neutronic performances of alternative fuels (Weapons grade plutonium -WGrPu-, Reactor grade plutonium RgrPuand Minor actinides -MA-) mixed with thorium were investigated in a Gas Turbine Modular Helium Reactor (GT-MHR). As the first step the performance of the original fuel, which uses uranium, was investigated and the initial effective multiplication factor (keff) value was calculated. According to this initial keff value, a 19% WGrPu - 81% Thorium mixture was found as the suitable mixture ratio. For the other alternative fuels it was found that none of the mixture ratios could reach the initial keff value of the original fuel. For these alternative fuels performances of three different mixture ratios (50% RGrPu - 50% Thorium, 90% RGrPu - 10% Thorium and 90% MA - 10% Thorium) were investigated. For the investigation, MCNP code was used with MONTEBURNS code, which acts as an interface between MCNP and ORIGEN 2.2 codes, was used for the time dependent calculations. All the calculations were done until the keff value reached to the 1,05 level. For the original fuel operation time was found as 475 days and burn-up value as 44,14 GWd/tHM. Nevertheless, for the 19% WGrPu - 81% Thorium mixture, the operation time and burn-up value was calculated as 975 days and 99,17 GWd/tHM, respectively. For the other alternative fuels, operation time and burn-up value for the 50% RGrPu 50% Th 175 days and 17,59 GWd/tHM, for 90% RGrPu 10% Th 1895 days and 174,64 GWd/tHM and for 90% MA 10% Th 75 days and 10,08 GWd/tHM, respectively.