GT-MHR project high-temperature reactor neutronic issues and ways to resolve them

The scope and trends of analytical and experimental activities aimed at studying neutronic characteristics of the GT-MHR high-temperature gas-cooled reactor are determined in compliance with the requirement for reliable validation of the GT-MHR design applying certified software tools.Risk factor existing in analytical validation of the GT-MHR neutronic characteristics consists in that the applicable neutronic analysis codes, which have been used up to the present time, are aimed at the HTGR designing and they have been tested mostly within analytical and experimental studies of HTGR with uranium fuel.Therefore, at the early stages of the GT-MHR nuclear design development it has already been determined that the experiments should be performed using critical test facilities and analytical benchmark-studies which are becoming quite relevant considering that plutonium fuel and erbium burnable poison are used.The report contains the validation program of the GT-MHR neutronic properties, the stages of its implementation and the main results obtained by now.