Аннотация
The paper considers an experimental device with a neutron converter [1], which provides a change in the neutron spectrum of the IGR reactor from thermal to fast. Successful testing requires a number of thermophysical calculations that sufficiently accurately simulate the thermal state of the experimental device and make it possible to justify the safe conditions of the experiment. The paper presents the results of non-stationary calculations of the thermal state of an experimental device with a neutron converter with energy release both in fuel and in structural materials that simulate nuclear fission energy in fuel elements and the effect of instantaneous and delayed gamma radiation on structural materials.