A high fidelity general purpose 3-D Monte Carlo particle transport program JMCT3.0

JMCT is a large-scale,high-fidelity,three-dimensional general neutron–photon–electron–proton transport Monte Carlo software system.It was developed based on the combinatorial geometry parallel infrastructure JCOGIN and the adaptive structured mesh infrastructure JASMIN.JMCT is equipped with CAD modeling and visualizes the image output.It supports the geometry of the body and the structured/unstructured mesh.JMCT has most functions,variance reduction techniques,and tallies of the traditional Monte Carlo particle transport codes.Two energy models,multi-group and continuous,are provided.In recent years,some new functions and algorithms have been developed,such as Doppler broadening on-thefly(OTF),uniform tally density(UTD),consistent adjoint driven importance sampling(CADIS),fast criticality search of boron concentration(FCSBC)domain decomposition(DD),adaptive control rod moving(ACRM),and random geometry(RG)etc.The JMCT is also coupled with the discrete ordinate SNcode JSNT to generate source-biasing factors and weight-window parameters.At present,the number of geometric bodies,materials,tallies,depletion zones,and parallel processors are sufficiently large to simulate extremely complicated device problems.JMCT can be used to simulate reactor physics,criticality safety analysis,radiation shielding,detector response,nuclear well logging,and dosimetry calculations etc.In particular,JMCT can be coupled with depletion and thermal-hydraulics for the simulation of reactor nuclear-hot feedback effects.This paper describes the progress in advanced modeling,high-performance numerical simulation of particle transport,multiphysics coupled calculations,and large-scale parallel computing.

Gamma ray multiplicity of a^(240)Pu solid sphere simulated by JMCT

Determining the mass of plutonium metal is an important research objective in the field of nuclear material accounting and control.Based on the 3D neutron and photon transport code JMCT(Jointed Monte Carlo Transport),the gamma ray multiplicity of ^(240)Pu was simulated in this study,and the average number of gamma rays leaking from ^(240)Pu solid spheres with different masses was also obtained.The simulation results show that there is a oneto-one correspondence between the average number of gamma rays and the mass of ^(240)Pu solid spheres in the range of 0.50–3.00 kg.This result provides a basis for using the average number of gamma rays to account for the mass of ^(240)Pu.