Experimental study on the neutron-physical parametrs of the flibe blanket of a thermonuclear reactor

Neutron physical parameters of blanket model on the basis of Li and Be fluoride salts have been studied by the different methods. Experimental model of salt blanket presented a sphere 400 mm in diameter filled with flibe (eutectic mixture of lithium and beryllium fluoride salts - LiF, BeF2 in the ratio 48 per 52 mol.%). In the experiment effect of lead and bismuth multiplication zone on the fission rate of 232Th and 235U has been studied. Multiplication zones of lead and bismuth are installed in the internal region of the model. A neutron generator, using DT-reaction, serves as a source of neutrons with the energy 14 MeV. The output of the neutron generator constituted approximately 1010 n/s. The conclusion is made that the use in measurements on blanket zone of modules of fission chamber and threshold activation indicators provides a possibility to obtain informative results with a low measurement error. Comparison of the experimental results with the calculation ones showed their considerable discrepancy, which is most probably connected with inaccuracy of used in calculation nuclear data of elements included in the composition of fuel assembly studied