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Title: Variable order spherical harmonic expansion scheme for the radiative transport equation using finite elements

Journal Article · · Journal of Computational Physics
 [1];  [1];  [2]
  1. Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom)
  2. Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio (Finland)

Highlights: {yields} We developed a variable order global basis scheme to solve light transport in 3D. {yields} Based on finite elements, the method can be applied to a wide class of geometries. {yields} It is computationally cheap when compared to the fixed order scheme. {yields} Comparisons with local basis method and other models demonstrate its accuracy. {yields} Addresses problems encountered n modeling of light transport in human brain. - Abstract: We propose the P{sub N} approximation based on a finite element framework for solving the radiative transport equation with optical tomography as the primary application area. The key idea is to employ a variable order spherical harmonic expansion for angular discretization based on the proximity to the source and the local scattering coefficient. The proposed scheme is shown to be computationally efficient compared to employing homogeneously high orders of expansion everywhere in the domain. In addition the numerical method is shown to accurately describe the void regions encountered in the forward modeling of real-life specimens such as infant brains. The accuracy of the method is demonstrated over three model problems where the P{sub N} approximation is compared against Monte Carlo simulations and other state-of-the-art methods.

OSTI ID:
21592609
Journal Information:
Journal of Computational Physics, Vol. 230, Issue 19; Other Information: DOI: 10.1016/j.jcp.2011.06.004; PII: S0021-9991(11)00353-6; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9991
Country of Publication:
United States
Language:
English