DOI: 10.57760/sciencedb.hjs.00040
title: Comparison of neutron transport calculation methods based on C5G7-MOX and preliminary analysis of sensitivity of MOC parameters
title: 基于C5G7-MOX的中子输运计算方法比较及MOC参数敏感性初步分析

description: [Background]: Method of Characteristics (MOC) is widely used in high-fidelity numerical simulation because of its powerful geometric processing ability and its ability to take into account calculation cost and accuracy. In addition to MOC, the common transport calculation methods also include Collision Probability Method (CP) and Interface Current Method (IC). [Purpose]: In this paper, the comparative analysis of MOC, CP and IC from method theory and numerical calculation is particularly important for evaluating their ability in pin-by-pin calculation. At the same time, in MOC calculation, different parameter selection will affect the calculation cost and calculation accuracy, so it is necessary to carry out sensitivity analysis to find the best parameter. [Methods]: In this paper, the three calculation methods are compared from the principle, and then the numerical calculation and the preliminary analysis of the sensitivity of MOC parameters are completed based on the 2D C5G7-MOX reference problem. [Results]: The calculation time and memory cost of MOC are 23.9min and 37.5MB respectively, and the relative error between MOC and reference solution is only 6.04×10-4. The computing time of CP and IC is 56.7 times and 15.6 times that of MOC, and the memory cost is 407.7 times and 32.8 times that of MOC, respectively. Based on the sensitivity analysis of MOC parameters, a set of suggested parameters are given: grid division is 6×6, pole Angle is GAUS and number is 2, and azimuth Angle is 30. The calculation time of this set of parameters is 45.4min, the memory cost is 264.7MB, the relative error is 5.9×10-5, and the normalized RMS error is 0.00255. [Conclusions]: The results show that MOC is superior to CP and IC in accuracy, efficiency and memory cost. Through the parameter sensitivity analysis, it is found that the grid division has the greatest influence on the calculation memory cost and calculation time, and the choice of polar Angle has the greatest influence on the calculation accuracy.
description: [Background]: Method of Characteristics (MOC) is widely used in high-fidelity numerical simulation because of its powerful geometric processing ability and its ability to take into account calculation cost and accuracy. In addition to MOC, the common transport calculation methods also include Collision Probability Method (CP) and Interface Current Method (IC). [Purpose]: In this paper, the comparative analysis of MOC, CP and IC from method theory and numerical calculation is particularly important for evaluating their ability in pin-by-pin calculation. At the same time, in MOC calculation, different parameter selection will affect the calculation cost and calculation accuracy, so it is necessary to carry out sensitivity analysis to find the best parameter. [Methods]: In this paper, the three calculation methods are compared from the principle, and then the numerical calculation and the preliminary analysis of the sensitivity of MOC parameters are completed based on the 2D C5G7-MOX reference problem. [Results]: The calculation time and memory cost of MOC are 23.9min and 37.5MB respectively, and the relative error between MOC and reference solution is only 6.04×10-4. The computing time of CP and IC is 56.7 times and 15.6 times that of MOC, and the memory cost is 407.7 times and 32.8 times that of MOC, respectively. Based on the sensitivity analysis of MOC parameters, a set of suggested parameters are given: grid division is 6×6, pole Angle is GAUS and number is 2, and azimuth Angle is 30. The calculation time of this set of parameters is 45.4min, the memory cost is 264.7MB, the relative error is 5.9×10-5, and the normalized RMS error is 0.00255. [Conclusions]: The results show that MOC is superior to CP and IC in accuracy, efficiency and memory cost. Through the parameter sensitivity analysis, it is found that the grid division has the greatest influence on the calculation memory cost and calculation time, and the choice of polar Angle has the greatest influence on the calculation accuracy.