METHOD FOR CONTROLLING THE THERMAL NEUTRON FLUX DENSITY AND A DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2022 - IPC G21C17/00 

FIELD: nuclear reactors.

SUBSTANCE: inventions group relates to means for controlling the thermal neutron flux density during high-temperature (1000-1800°C) irradiation of fuel samples (FS) as part of an irradiation device capsule in a research nuclear reactor. In the method, the fissile detector is delivered along the transport highway under the influence of gas to the place of irradiation of fuel samples, and upon completion of irradiation, the fissile detector is evacuated to the place where the activity of the reference radionuclides of the fissile detector is registered. The device includes a transport highway with a fissile detector located in it and a gamma spectrometric device. The transport highway is equipped with a system of electrovalves. To ensure a specified movement of the fissile detector along the transport line, a gas-regulated two-ended capillary is used that passes through the capsule with fuel samples. The section of the transport line inside the capsule is made of refractory material, and in its internal volume there is a choke washer made of refractory material with a flow area that ensures the delivery of the fissile detector into the internal volume of the capsule, fixation of the fissile detector for the period of its irradiation with reactor neutrons and subsequent evacuation of the fissile detector to gamma - spectrometric device.

EFFECT: increasing the reliability of monitoring the energy release and burnup in FS at any stage of irradiation by accelerating, simplifying and improving the accuracy of measuring the thermal neutron flux density.

3 cl, 1 dwg