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An hp-angular adaptivity with the discrete ordinates method for Boltzmann transport equation

  • Ni Dai (School of Nuclear Science and Engineering, North China Electric Power University) ;
  • Bin Zhang (School of Nuclear Science and Engineering, North China Electric Power University) ;
  • Xinyu Wang (School of Nuclear Science and Engineering, North China Electric Power University) ;
  • Daogang Lu (School of Nuclear Science and Engineering, North China Electric Power University) ;
  • Yixue Chen (School of Nuclear Science and Engineering, North China Electric Power University)
  • Received : 2022.06.08
  • Accepted : 2022.10.19
  • Published : 2023.02.25

Abstract

This paper describes an hp-angular adaptivity algorithm in the discrete ordinates method for Boltzmann transport applications with strong angular effects. This adaptivity uses discontinuous finite element quadrature sets with different degrees, which updates both angular mesh and the degree of the underlying discontinuous finite element basis functions, allowing different angular local refinement to be applied in space. The regular and goal-based error metrics are considered in this algorithm to locate some regions to be refined. A mapping algorithm derived by moment conservation is developed to pass the angular solution between spatial regions with different quadrature sets. The proposed method is applied to some test problems that demonstrate the ability of this hp-angular adaptivity to resolve complex fluxes with relatively few angular unknowns. Results illustrate that a reduction to approximately 1/50 in quadrature ordinates for a given accuracy compared with uniform angular discretization. This method therefore offers a highly efficient angular adaptivity for investigating difficult particle transport problems.

Keywords

Acknowledgement

This work was supported by the National Natural Science Foundation of China (11975097).

References

  1. E.E. Lewis, W.F. Miller, Computational Methods of Neutron Transport, John Wiley & Sons, Inc., New Jersey, 1984. 
  2. H.K. Park, Coupled Space-Angle Adaptivity and Goal-Oriented Error Control for Radiation Transport Calculations, Georgia Institute of Technology, Georgia, 2006. 
  3. K. Rupp, T. Grasser, et al., Adaptive Variable-Order Spherical Harmonics Expansion of the Boltzmann Transport Equation, International Conference on Simulation of Semiconductor Processes and Devices, Osaka, 2011. 
  4. M.A. Goffin, A.G. Buchan, et al., Goal-based angular adaptivity applied to the spherical harmonics discretisation of the neutral particle transport equation, Ann. Nucl. Energy 71 (9) (2014) 60-80.  https://doi.org/10.1016/j.anucene.2014.03.030
  5. S. Dargaville, A.G. Buchan, et al., Angular adaptivity with spherical harmonics for Boltzmann transport, J. Comput. Phys. 397 (2019), 108846. 
  6. A.G. Buchan, C.C. Pain, et al., Self-adaptive spherical wavelets for angular discretizations of the Boltzmann transport equation, Nucl. Sci. Eng. 158 (3) (2008) 244-263.  https://doi.org/10.13182/NSE08-A2751
  7. M.A. Goffin, A.G. Buchan, S. Dargaville, et al., Goal-based angular adaptivity applied to a wavelet-based discretisation of the neutral particle transport equation, J. Comput. Phys. 281 (2015) 1032-1062.  https://doi.org/10.1016/j.jcp.2014.10.063
  8. S. Dargaville, A.G. Buchan, et al., Scalable angular adaptivity for Boltzmann transport, J. Comput. Phys. 406 (2019), 109124. 
  9. S. Dargaville, R.P. Smedley-Stevenson, P.N. Smith, et al., Goal-based angular adaptivity for Boltzmann transport in the presence of ray-effects, J. Comput. Phys. 421 (2020), 109759. 
  10. J.C. Stone, Adaptive Discrete-Ordinates Algorithms and Strategies, Texas A&M University, Texas, 2007. 
  11. J.J. Jarrell, An Adaptive Angular Discretization Method for Neutral-Particle Transport in Three-Dimensional Geometries, Texas A&M University, Texas, 2010. 
  12. C.Y. Lau, M.L. Adams, Discrete ordinates quadratures based on linear and quadratic discontinuous finite elements over spherical quadrilaterals, Nucl. Sci. Eng. 185 (1) (2017) 36-52.  https://doi.org/10.13182/NSE16-28
  13. N. Dai, B. Zhang, Y.X. Chen, Discontinuous finite-element quadrature sets based on icosahedron for the discrete ordinates method, Nucl. Eng. Technol. 52 (6) (2020) 1137-1147.  https://doi.org/10.1016/j.net.2019.11.025
  14. C.Y. Lau, Adaptive Discrete-Ordinates Quadratures Based on Discontinuous Finite Elements over Spherical Quadrilaterals, Texas A&M University, Texas, 2016. 
  15. N. Dai, B. Zhang, Y.X. Chen, et al., Adaptive discontinuous finite element quadrature sets over an icosahedron for discrete ordinates method, Nucl. Sci. Tech. 32 (2021) 98. 
  16. J. Kophazi, D. Lathouwers, A space-angle DGFEM approach for the Boltzmann radiation transport equation with local angular refinement, J. Comput. Phys. 297 (2015) 637-668.  https://doi.org/10.1016/j.jcp.2015.05.031
  17. N. Dai, B. Zhang, et al., High-degree discontinuous finite element discrete quadrature sets for the Boltzmann transport equation, Prog. Nucl. Energy 153 (2022), 104403. 
  18. Y. Wang, J. Ragusa, Application of hp adaptivity to the multigroup diffusion equations, Nucl. Sci. Eng. 161 (1) (2009) 22-48.  https://doi.org/10.13182/NSE161-22
  19. K. Atkinson, W. Han, Spherical Harmonics and Approximations on the Unit Sphere: an Introduction, Springer Verlag, Berlin Heidelberg, 2012. 
  20. B.G. Carlson, C.E. Lee, Mechanical Quadrature and the Transport Equation, Los Alamos Scientific Lab., 1961. Report LAMS-2573. 
  21. W.F. Walters, Use of the Chebyshev-Legendre Quadrature Set in Discrete Ordinates Codes, Los Alamos Scientific Lab., 1985. Report LA-UR-87-3621. 
  22. B. Zhang, L. Zhang, C. Liu, et al., Goal-oriented regional angular adaptive algorithm for the SN equations, Nucl. Sci. Eng. 189 (2) (2018) 120-134.  https://doi.org/10.1080/00295639.2017.1394085
  23. K. Kobayashi, N. Sugimura, Y. Nagaya, 3D radiation transport benchmark problems and results for simple geometries with void region, Prog. Nucl. Energy 39 (2) (2001) 119-144, 2001. https://doi.org/10.1016/S0149-1970(01)00007-5