Continuum Radiative Heat Transfer Modeling in Media Consisting of Optically Distinct Components in the Limit of Geometrical Optics

Abstract

a b s t r a c tContinuum-scale equations of radiative transfer and corresponding boundary conditions are derived for a general case of a multi-component medium consisting of arbitrary-type, non-isothermal and non-uniform components in the limit of geometrical optics. The link between the discrete and continuum scales is established by volume averaging of the discrete-scale equations of radiative transfer by applying the spatial averaging theorem. Precise definitions of the continuum-scale radiative properties are formulated while accounting for the radiative interactions between the components at their interfaces. Possible applications and simplifications of the presented general equations are discussed.Published by Elsevier Ltd.

Radiative characterization of random fibrous media with long cylindrical fibers: Comparison of single- and multi-RTE approaches

“…They average the RTEs for each phase (air and fiber) in the limit of geometrical optics and introduce the appropriate discretescale boundary conditions at the phase interface. This leads to two coupled volume-averaged RTEs as described in [12,13,17] and given by,…”

“…The collision-based Monte Carlo ray-tracing method (MCRT) is used in combination with radiative distribution functions for semitransparent media [7,14,17,36] . A large number of stochastic rays N distributed within REV of the fibrous samples are emitted.…”

“…A theoretical multi-RTE approach, i.e. averaged radiative transfer equations are valid in each individual phase, has recently been introduced within the limit of geometrical optics assumptions [12][13][14][15][16][17][18] . This approach has the ability to incorporate realistic and morphologically complex media.…”

Continuum radiative heat transfer modeling in media consisting of optically distinct components in the limit of geometrical optics

“…Continuum-scale RTEs were derived for a medium consisting of large opaque and spherical particles suspended in a participating gas phase [14], for a medium consisting of two arbitrary-type and arbitrary-shaped components [15][16][17][18], and formulated for a medium consisting of two arbitrary-shaped semitransparent components [9]. In this paper, we generalize the analysis presented in [18] to multi-component media consisting of M arbitrary-type and arbitrary-shaped components in the limit of geometrical optics [19]. A system of continuumscale RTEs and the corresponding boundary conditions are derived by applying volume averaging to discrete-scale RTEs and boundary conditions.…”

Discrete vs. continuum-scale simulation of radiative transfer in semitransparent two-phase media

“…[20] and generalized to an arbitrary number of phases in Ref. [21]. In a prior study Consalvi et al [22] carried out a similar averaging procedure limited to gray, diffuse, spherical particles.…”