Research On Measurement Method Of Neutron Characteristic Parameters To High Intensity Of D-T Neutron Generator

Controlled nuclear fusion technology is a highly anticipated energy solution,there is still a period of time before the commercial demonstration of fusion reactors due to the limitation of current technical conditions.For fusion reactors key technologies such as tritium breeding efficiency,blanket structure design,material activation and damage still need to be further studied.The high intensity of D-T neutron generator can generate 14 MeV fusion neutrons,which is consistent with the neutron irradiation environment in the fusion reactor can be used for advanced nuclear energy technology research.At the same time,it can also be used in neutron photography and nondestructive testing(NDT),nuclear medicine and radiotherapy,drug inspection and security,and other nuclear technology applications.These frontier research fields have a huge demand for high intensity of D-T neutron generator.This paper focuses on the design,construction and experimental operation of the fast neutron measurement system on the High Intensity of D-T Neutron Generator(HINEG)device,the research on radiation field modeling and characteristic parameter measurement methods are carried out.The main research contents are as follows:1.The calculation methods of neutron energy spectrum,neutron angular distribution and integral neutron yield are studied under different thicknesses of tritium target on the basis of summarizing and analyzing the kinematic equations of T(d,n)4He nuclear reaction.With the help of GEANT4 Monte Carlo software,the experimental hall and rotating target model are established,and the simulation calculation of the radiation field characteristic parameters of the HlNEG device is completed.2.In order to optimize the experimental space of the HINEG device and improve the neutron flux measurement accuracy,a set of contra-angle 45° recoil proton coincidence telescope system is designed for neutron flux monitor.A neutron flux monitoring measurement system with three methods and four measurement means is built,including Al/Nb activation foil,238U fission ionization chamber and 4H-SiC semiconductor neutron detector.The error factors affecting the measurement results are studied,the consistency of measurement results is good.3.Aiming at the problem of neutron spectrum measurement of high intensity of D-T neutron generator,a scheme of using EJ301 liquid scintillator detector for neutron spectrum measurement is proposed.The focus of study is on the n/y discrimination,the spectrum unfold algorithm and the energy res,ponse function calculation method.The method of small-batch Kmeans++ clustering realizes n/γonline automatic classification of signals,and spectral unfold algorithm based on generalized regression neural network has better performance of neutron energy spectrum solution.The above research provides a solution for the measurement of the neutron characteristic parameters of HINEG device,and the feasibility of above methods is verified through experiments.This paper preliminarily builds a fast neutron nuclear measurement system which has positive significance for the application of HlNEG device and the development of neutron physics experiments.