Study on the Attenuation Method of Discrete Ordinate Ray Effect Based on Multiple Collision Source

Zheng Zheng; Li Xiang; Mei Qiliang; Li Hui; Wang Mengqi

doi:10.13832/j.jnpe.2025.01.0036

Volume 46 Issue 1

Feb. 2025

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Zheng Zheng, Li Xiang, Mei Qiliang, Li Hui, Wang Mengqi. Study on the Attenuation Method of Discrete Ordinate Ray Effect Based on Multiple Collision Source[J]. Nuclear Power Engineering, 2025, 46(1): 36-40. doi: 10.13832/j.jnpe.2025.01.0036

Citation:

Zheng Zheng, Li Xiang, Mei Qiliang, Li Hui, Wang Mengqi. Study on the Attenuation Method of Discrete Ordinate Ray Effect Based on Multiple Collision Source[J]. Nuclear Power Engineering, 2025, 46(1): 36-40. doi: 10.13832/j.jnpe.2025.01.0036

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Study on the Attenuation Method of Discrete Ordinate Ray Effect Based on Multiple Collision Source

doi: 10.13832/j.jnpe.2025.01.0036

Shanghai Nuclear Engineering Research and Design Institute Co., Ltd., Shanghai, 200233, China

Received Date: 2024-04-09
Rev Recd Date: 2024-05-09
Publish Date: 2025-02-15

Abstract

Abstract

This study aims to explore the use of the Monte Carlo (MC) method to calculate multi-collision source distributions, so as to mitigate the ray effect in the discrete ordinates (SN) method, particularly in models with localized sources, low-density regions, or vacuum areas. The distribution of multiple collision sources is calculated by MC method, and the method of reducing the ray effect of multiple collision sources and first collision sources is preliminarily verified and analyzed by Kobayashi benchmark problem. Through hybrid parallel technique (message passing interface MPI + open multiprocessor OpenMP), the computational efficiency is improved and the load imbalance problem is reduced. The study shows that the MC multi-collision source method effectively suppresses the ray effect in localized source problems within the SN method, significantly reducing non-physical oscillations and improving computational accuracy. When the number of collisions exceeds three, the computational deviation is reduced to below 10%. Furthermore, the use of hybrid parallel computing resulted in a parallel efficiency exceeding 80% with 120 threads. Although this method has a slight drawback in terms of computational time, it shows great potential for addressing complex geometries and physical conditions, making it a promising approach for reducing the ray effect.
- Monte Carlo,
- Discrete ordinate,
- Multiple collision source,
- First collision source,
- Ray effect,
- Hybrid parallel

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References(13)

References

[1]	CARLSON B G. Solution of the transport equation by sn approximations, LA-1891[R]. Los Alamos: Los Alamos National Lab. , 1955.
[2]	LATHROP K D. Ray effects in discrete ordinates equations[J]. Nuclear Science and Engineering, 1968, 32(3): 357-369. doi: 10.13182/NSE68-4
[3]	ALCOUFFE R E. A first collision source method for coupling Monte Carlo and discrete ordinates for localized source problems[M]//ALCOUFFE R, DAUTRAY R, FORSTER A, et al. Monte-Carlo Methods and Applications in Neutronics, Photonics and Statistical Physics. Berlin: Springer, 1985: 352-366.
[4]	胡也,陈义学,张斌,等. 基于首次碰撞源方法的多维SN射线效应研究[J]. 原子能科学技术,2013, 47(S1): 9-14.
[5]	杨超,李志鹏,于涛,等. 基于全局因子修正首次碰撞源的射线效应方法研究[J]. 核动力工程,2023, 44(3): 54-58.
[6]	张斌. 基于目标导向的角度自适应射线效应消除方法研究[D]. 北京: 华北电力大学,2018.
[7]	王新宇,张斌,陈义学. 基于多次碰撞源的屏蔽计算方法研究[J]. 原子能科学技术,2020, 54(5): 811-819. doi: 10.7538/yzk.2019.youxian.0557
[8]	HERRING N F, YESSAYAN R A, BEYER K A, et al. Ray effects mitigation through monte carlo coupling for detector problems[C]//International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering, M and C. Portland: American Nuclear Society, 2019: 2228-2237.
[9]	ZHANG G C, HAO C Y, LIU K, et al. Ray effects mitigation using the Monte Carlo first collision source method and application to the Kobayashi benchmark problems[J]. Annals of Nuclear Energy, 2022, 169: 108902. doi: 10.1016/j.anucene.2021.108902
[10]	KOBAYASHI K, SUGIMURA N, NAGAYA Y. 3D radiation transport benchmark problems and results for simple geometries with void region[J]. Progress in Nuclear Energy, 2001, 39(2): 119-144. doi: 10.1016/S0149-1970(01)00007-5
[11]	DENG L, LI G, ZHANG B Y, et al. A high fidelity general purpose 3-D Monte Carlo particle transport program JMCT3.0[J]. Nuclear Science and Techniques, 2022, 33(8): 108. doi: 10.1007/s41365-022-01092-0
[12]	CHENG T P, MO Z Y, YANG C, et al. JSNT-S: a parallel 3D discrete ordinates radiation transport code on structured mesh[C]//2018 26th International Conference on Nuclear Engineering. London: ASME, 2018.
[13]	KONNO C. TORT solutions with FNSUNCL3 for Kobayashi's 3D benchmarks[J]. Progress in Nuclear Energy, 2001, 39(2): 167-179. doi: 10.1016/S0149-1970(01)00010-5