A comparison of triangular and quadrilateral finite element meshes for Bragg edge neutron transmission strain tomography
Authors: Aggarwal Riya , Lamichhane Bishnu , Meylan Mike , Wensrich Chirs 
Published: August 2020

A wavelength resolved measurement technique used in neutron imaging applications is known as energy-resolved neutron transmission imaging. This technique of reconstructing residual strain maps provides high spatial resolution measurements of strain distribution in polycrystalline materials from sets of Bragg edge measurement images. Strain field reconstructions obtained from both triangular and quadrilateral finite element meshes are compared. The reconstruction is approached via a least square method and relies on the inversion of the longitudinal ray transform, which has uniqueness issues.
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