Coupling between radiative transport and diffusion approximation for enhanced near-field photon-migration modeling...

Area of Science:

• Physics
• Computational Physics
• Photonics

Background:

• Coupling transport theory and diffusion approximation in hybrid models for photon migration is computationally complex and can be inaccurate.
• Existing methods struggle with physically consistent integration of these two physics domains.

Purpose of the Study:

• To develop a physically consistent coupling method for linking photon transport and diffusion physics.
• To enhance the description of near-field photon migration in subdomain-based hybrid models.
• To improve computational efficiency and accuracy in modeling photon transport.

Main Methods:

• A transient photon kinetics approach is used to link transport and diffusion physics.
• An auxiliary time-domain diffusion solution provides the distribution of fully diffusive photons at a transition time.
• This solution acts as a source for both the transport and diffusion equations, enabling independent calculation of early and late photodensities.

Main Results:

• The proposed method achieves a physically consistent coupling between transport and diffusion equations.
• It allows for independent calculation of early-stage photodensities (from transport) and late-stage photodensities (from diffusion).
• Numerical simulations validate the scheme for a cubic geometry, demonstrating its effectiveness.

Conclusions:

• The developed method offers a computationally efficient and physically accurate way to model near-field photon migration.
• It successfully integrates transport and diffusion physics for comprehensive steady-state modeling.
• This approach advances hybrid modeling techniques in photonics and computational physics.