Assembly-Homogenized Calculation based on NECP-MCX and Its Application in HPR1000
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摘要: 基于蒙特卡罗的组件计算程序可以处理复杂几何问题，同时不需要确定论组件计算程序中的共振自屏计算，但是蒙特卡罗组件计算程序在扩散系数和不连续因子的产生上存在一定困难。因此，基于连续能量蒙特卡罗粒子输运计算程序NECP-MCX，开发了组件均匀化少群常数产生功能，使用严格考虑中子各向异性的累积徙动面积法产生扩散系数，利用基模修正考虑中子泄漏对中子能谱的影响，提出网格面计数方法计算修正的组件不连续因子。根据VERA二维组件问题对网格面计数方法进行了验证，并将NECP-MCX用于我国自主化核电“华龙一号”零功率启动物理试验的模拟计算。结果表明，与设计值对比，临界硼浓度、等温温度系数、控制棒积分价值的计算偏差均符合工业限值要求。该程序可以产生可靠的组件均匀化少群常数，计算精度符合工程计算的要求，为该程序在新型反应堆中的进一步应用打下了坚实基础。
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关键词:
- 少群常数 /
- NECP-MCX /
- 蒙特卡罗 /
- 华龙一号（HPR1000）
Abstract: The assembly code based on the Monte Carlo method can handle problems with complicated geometry and avoid the resonance self-shielding calculation in the deterministic assembly code. However, the Monte Carlo assembly code has certain difficulties when generating diffusion coefficient and assembly discontinuous factors. Therefore, the capability for the generation of assembly-homogenized few-group constants is developed based on the continuous-energy Monte Carlo particle transport code NECP-MCX. The cumulative migration area method, which treats the anisotropy of neutron explicitly, is adopted to generate the diffusion coefficient; the fundamental mode approximation is used to consider the effect of neutron leakage on the neutron spectrum; the approach named as the mesh-surface tally is proposed to calculate the corrected assembly discontinuous factors. The mesh-surface tally approach is verified through VERA 2D assembly problems and the NECP-MCX is adopted to simulate the physics start-up test of the home-developed HPR1000 reactor. The results show that the biases of critical boron concentrations, the isothermal temperature coefficients, and the control rod bank worth values satisfy the limited value when compared to the design report. The NECP-MCX has the ability to generate reliable assembly-homogenized few-group constants of which accuracy satisfies the requirement of engineering calculation, laying a solid foundation for the further application of NECP-MCX in next-generation reactors.-
Key words:
- Few-group constants /
- NECP-MCX /
- Monte Carlo /
- HPR1000
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图 2 组件归一化功率相对误差统计
Figure 2. Statistic Results of Assembly Normalized Power Relative Errors
表 1 不连续因子的计算结果对比
Table 1. Comparison of Discontinuous Factors
问题 能群 不开启网格面
计数的误差/%开启网格面
计数的误差/%VERA 2B 快群 −0.789 0.022 VERA 2B 热群 5.852 0.099 VERA 2F 快群 −0.747 0.038 VERA 2F 热群 6.349 0.188 VERA 2G 快群 −0.771 0.022 VERA 2G 热群 6.469 0.238 VERA 2P 快群 −0.866 −0.072 VERA 2P 热群 5.708 −0.513 
下载: 导出CSV
表 2 临界硼浓度的计算结果对比
Table 2. Comparison of Critical Boron Concentrations
试验项目 与设计值
的偏差/
ppm与Bamboo-C
计算值的
偏差/ppmARO状态 −31.3 −6.5 R棒组全插状态 −30.6 −6.0 R、G1棒组全插状态 −31.9 −6.3 G1棒组全插状态 −31.4 −6.5 G1、G2棒组全插状态 −33.7 −6.5 G1、G2、N1棒组全插状态 −38.1 −7.5 G1、G2、N1、N2棒组全插状态 −30.5 −3.2 R、G1、G2、N1、N2棒组全插状态 −28.1 −0.8 R、G1、G2、N1、N2、SC棒组全插状态 −31.0 −2.0 R、G1、G2、N1、N2、SC、SB棒组全插状态 −34.5 −4.3 ARI-B08(该处R棒组提出)状态 −45.4 −8.0 1ppm=10−6
下载: 导出CSV
表 3 等温温度系数的计算结果对比
Table 3. Comparison of Isothermal Temperature Coefficients
试验项目 与设计值的
偏差/(pcm ∙ K−1)与Bamboo-C计算值的
偏差/(pcm ∙ K−1)ARO状态 −0.337 0.048 R棒组全插状态 −1.035 0.008 R、G1棒组全插状态 −1.069 −0.037 1pcm=10−5
下载: 导出CSV
表 4 控制棒积分价值的计算结果对比
Table 4. Comparison of Control Rod Integral Worth
试验项目 与设计
值的偏
差/%与Bamboo-C
计算结果的
偏差/%稀释法计算R棒组 0.2 −0.3 稀释法计算G1棒组（R棒组全插） 4.7 0.9 稀释法计算SB棒组 −0.7 −0.4 换棒法计算SA棒组 0.1 −0.8 换棒法计算N2棒组 −1.8 −1.7 换棒法计算N1棒组 1.6 0.5 换棒法计算G2棒组 0.1 −0.1 换棒法计算SC棒组 1.9 1.3 换棒法计算G1棒组 −0.2 0.2 换棒法计算50%功率下落棒试验所选棒束
（G03和J13位置处的SB棒组）0.9 −0.1 换棒法计算落棒试验所选棒束
（G13位置处的SB棒组）1.5 0.4 稀释法计算G1棒组 3.2 0.2 稀释法计算G2棒组
（G1棒组全插）2.9 0.1 稀释法计算N1棒组
（G1、G2棒组全插）6.4 1.6 稀释法计算N2棒组
（G1、G2、N1棒组全插）−3.0 −2.1 稀释法计算R棒组
（G1、G2、N1、N2棒组全插）−1.2 −1.1 稀释法计算SC棒组
（R、G1、G2、N1、N2棒组全插）4.4 1.6 稀释法计算SB棒组
（R、G1、G2、N1、N2、SC棒组全插）2.3 2.0
下载: 导出CSV
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[1] TOHJOH M, WATANABE M, YAMAMOTO A. Application of continuous-energy Monte Carlo code as a cross-section generator of BWR core calculations[J]. Annals of Nuclear Energy, 2005, 32(8): 857-875. doi: 10.1016/j.anucene.2005.01.002 [2] FRIDMAN E, LEPPÄNEN J. On the use of the Serpent Monte Carlo code for few-group cross section generation[J]. Annals of Nuclear Energy, 2011, 38(6): 1399-1405. doi: 10.1016/j.anucene.2011.01.032 [3] PARK H J, SHIM H J, JOO H G, et al. Generation of few-group diffusion theory constants by Monte Carlo code McCARD[J]. Nuclear Science and Engineering, 2012, 172(1): 66-77. doi: 10.13182/NSE11-22 [4] 李满仓. 连续能量蒙特卡罗方法组件均匀化研究[D]. 北京: 清华大学, 2012. [5] 吴高晨. 基于RMC的连续能量蒙特卡罗均匀化与群常数产生研究[D]. 北京: 清华大学, 2018. [6] 杜夏楠,吴宏春,郑友琦. 蒙特卡罗方法在快堆组件参数计算中的应用[J]. 核动力工程,2014, 35(S2): 67-70. [7] KORD S. SMITH Nodal diffusion methods and lattice physics data in LWR analyses: Understanding numerous subtle details[J]. Progress in Nuclear Energy, 2017, 101: 360-369. [8] 郑琪,沈炜,贺清明,等. 基于NECP-MCX的蒙特卡罗-确定论耦合及权窗网格粗化方法研究[J]. 核动力工程,2021, 42(2): 202-207. [9] LIU Z Y, SMITH K, FORGET B, et al. Cumulative migration method for computing rigorous diffusion coefficients and transport cross sections from Monte Carlo[J]. Annals of Nuclear Energy, 2018, 112: 507-516. doi: 10.1016/j.anucene.2017.10.039 [10] REDMOND E L. Multigroup cross section generation via Monte Carlo methods[D]. Cambridge: Massachusetts Institute of Technology, 1997. [11] DAWN W C, ORTENSI J, DEHART M D, et al. Comparison of generation of higher-order neutron scattering cross sections[R]. Idaho Falls: Idaho National Laboratory, 2020. [12] LEPPÄNEN J, PUSA M, FRIDMAN E. Overview of methodology for spatial homogenization in the Serpent 2 Monte Carlo code[J]. Annals of Nuclear Energy, 2016, 96: 126-136. doi: 10.1016/j.anucene.2016.06.007 [13] STAMM’LER R J, ABBATE M J. Methods of steady-state reactor physics in nuclear design[M]. London: Academic Press, 1983: 151-152. [14] 田超,郑友琦,李云召,等. 压水堆各向异性散射的输运修正方法研究[J]. 原子能科学技术,2017, 51(9): 1599-1605. [15] LIN C S, YANG W S. An assessment of the applicability of multigroup cross sections generated with Monte Carlo method for fast reactor analysis[J]. Nuclear Engineering and Technology, 2020, 52(12): 2733-2742. doi: 10.1016/j.net.2020.05.029 [16] SMITH K S. Assembly homogenization techniques for light water reactor analysis[J]. Progress in Nuclear Energy, 1986, 17(3): 303-335. doi: 10.1016/0149-1970(86)90035-1 [17] GODFREY A T. VERA core physics benchmark progression problem specifications, revision 4[R]. Oka Ridge: Oka Ridge National Laboratory, 2014. [18] 万承辉,李云召,郑友琦,等. 压水堆燃料管理软件Bamboo-C研发及工业确认[J]. 核动力工程,2021, 42(5): 15-22. -
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