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arXiv · 1907.13013

Acceleration of the Sn Equations with Highly Anisotropic Scattering using the Fokker-Planck Equation

Japan K. Patel·James S. Warsa·Anil K. Prinja
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Abstract

The discrete ordinates method can model forward-peaked transport problems accurately. However, convergence of discrete ordinates solution can become arbitrarily slow upon use of standard iterative procedures like source iteration and GMRES. Standard zeroth and first moment-based acceleration methods like nonlinear diffusion acceleration and diffusion synthetic acceleration are ineffective in accelerating such problems because these methods do not correct higher order Legendre-moments of angular flux. We explore the idea of using Fokker-Planck as a preconditioner to accelerate forward-peaked transport problems in this paper.

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Japan K. Patel, James S. Warsa, Anil K. Prinja. 2019-07-30. Acceleration of the Sn Equations with Highly Anisotropic Scattering using the Fokker-Planck Equation. https://arxiv.org/abs/1907.13013

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