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Updated: May 2, 2026

The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Closed-form solution of the steady-state photon diffusion equation in the presence of absorbing inclusions
Abstract:
We have developed a theoretical model for photon migration through scattering media in the presence of an absorbing inhomogeneity. A closed-form solution for the average diffuse intensity has been obtained through an iterative approximation scheme of the steady-state diffusion equation. The model describes absorbing defects in a wide range of values. Comparisons with the results of Monte Carlo simulations show that the error of the model is lower than 3% for size inclusion lower than 4 mm and absorption contrast up to the threshold value of the "black defect." The proposed model provides a tractable mathematical basis for diffuse optical and photoacoustic tomographic reconstruction techniques.
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