Volume energy release in directional irradiation of an absorbing and scattering layer with mirror-diffusion boundaries

Algebraic relationships are derived for investigating the energy release as a function of the optical depth of a semitransparent layer with an allowance for the volume multiple anisotropic scattering and the specular–diffusion character of reflection from the boundaries when the layer is irradiated with a directional flux. The solution obtained makes it possible to use the available data on the hemispherical and directional-hemispherical coefficients of reflection and transmission of the absorbing and scattering layer and of the chosen boundaries. A parametric analysis of the solution for a semi-infinite layer is used to determine the characteristic behavior of the energy release function, connected with the absorbed energy concentration in the surface layer, as the volume scattering and the coefficient of reflection from the irradiated boundary increase. It is shown that an energy release maximum develops at a certain depth for high values of the scattering albedo and the specular component of the coefficient of reflection from the boundary.