Monte Carlo Simulation of Ground Environment of Induced Radioactivity Radiation Produced by Neutrons of Nuclear Explosion
SHANG Peng;HUANG Liuxing;NIU Shengli;ZUO Yinghong;ZHU Jinhui;Northwest Institute of Nuclear Technology;
To simulate the induced radioactivity radiation environment in the ground of explosion area produced by neutrons of nuclear explosion, a two-step calculation method based on Monte Carlo method is proposed. The first step is to build a layered statistical model of neutron transport and γ radiator source model. In the second step, the model parameter conversion technology is used to combine the two model parameters and carry out simulation calculation. The multi process integrated fine simulation of “neutron transport-nuclide activation-photon radiation-dose detection” is realized. The variation of radionuclide density in neutron activated soil with depth is given by Monte Carlo simulation. The influences of soil layer thickness and radius of γ layered-radiator source model on the ground induced radioactivity is analyzed. The calculation results show that when the soil layer thickness of γ radiator source model is 60 cm and the radius is 40 m, the relative devaition meets the requirements of the simulation results. The variations of dose rate and radionuclide dose contribution ratio with time in γ induced radioactivity decay at the height of 1 m above the ground are calculated by two-step calculation method when the explosion height of a typical hydrogen bomb is 200 m.