Radiative Beam in Absorbing Media Theory
The Radiative Beam in Absorbing Media Interface is available in 2D, 2D axisymmetric, and 3D components to model the propagation and the attenuation of an incident light within a semitransparent material. The radiative intensity of the beam is described by the Beer-Lambert Law, which corresponds to the radiative transport equation (RTE) under the following hypothesis:
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The radiative beam in the absorbing medium is collimated and each beam propagates always in the same direction.
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The light experiences no refraction, reflection, or scattering within the material itself.
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There is no significant emission of the material in the wavelength range of the incident light. This applies well to laser beams, whose wavelength is in general much shorter than the one of the radiation emitted by the medium.
In these conditions, the radiative intensity Ii (SI unit: W/m2) of the ith beam through the material decreases as the beam propagates and is absorbed by the medium. This is described by the Beer-Lambert Law equation:
where ei is the orientation of the ith beam, and κ is the absorption coefficient (SI unit: m–1) of the medium.
The radiative heat source Qr (SI unit: W/m3), corresponding to the energy deposited by the radiative beam, is defined by:
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