Preliminary study for alternative conceptual core design of the MTR research reactor

Abstract

The utilization of the research reactor is increasingly widespread, especially for radioisotope production and testing of advanced materials and preference to use a compact core. The reactor core design has been determined on the maximum thermal flux in the middle of the core per MW. BATAN has designed several alternative research reactor cores. The purpose of this research reactor is to obtain the optimum reactor core configurations with the criteria to have a thermal neutron flux in the centre of the core with minimum of 1.0×1015 n/cm2 s. Power level of the research reactor is 60 MWthwith U9Mo/Al fuel 85 cm of height. Design of plate-type fuels with a higher core results in the heat transfer to the coolant optimal. All 16 fuel assemblies and the 4 control rodsare inserted into the core for this reactor. The core design calculations were carried out with the WIMSD-5B and BATAN-FUEL codes. Conceptual design calculation results show that the core configuration with 5 × 5 grids, all the fresh fuel, fuel loading of 470 g, a D2O reflector, a maximum thermal neutron flux in the central core is 1.09 x 1015 n/cm2s and the cycle length is 33 days. The reactor core design is the most optimal for MTR type. For the equilibrium core, a fuel loading of 600 g results in the maximum thermal flux of 1.07x1015 n/cm2s and the two safety rods should be used in the core.