Radiation Transfer in Fibrous Medium with Fiber Orientation

This paper deals with a pseudo-continuous model for the prediction of radiative transfer in fibrous media. The proposed model incorporates the fiber orientation and effective fiber length in the determination of the radiative properties of the medium. Applicability of the model in the prediction of radiative properties of fibrous media is justified on the basis of experimental findings. In this study, a planar fibrous medium in which every fiber is oriented parallel to the boundaries stratifying the medium is adopted as a test specimen. The scattered radiation from a single fiber taken out of the medium is first measured to determine the complex refractive index of the fiber material. The experimentally determined complex refractive index is then used to predict the radiative properties of the medium. The radiation transfer in the specimen that is calculated using the predicted radiative properties is seen to agree well with the corresponding experimental results.