A special neutron diagnostic system is proposed that facilitates the measurement of neutron fluxes and spectra in the neutronics and tritium production-test blanket module (NTTBM) without interrupting the operation of the International Thermal-nuclear Experimental Reactor (ITER),for studying the multiplication rate in the neutron multiplier and breeding ratio of tritium in the breeder.This system includes an encapsulated foil activation system,micro-fission chamber detectors (MFC),and a compact neutron spectrometer using a natural diamond detector (NDD).A helium coolant loop with a reasonable diameter is designed carefully for every measurement channel that ensures that the neutron detectors and preamplifiers would work well under a high temperature scenario and that the filling rates of the neutron multiplier (beryllium pebble)and tritium breeder material (Li4Si04) would not decrease excessively (the expected value≥80%)due to the dimensions of the helium coolant loop.
展开▼