TY - JOUR
T1 - Radiation transfer in fibrous media with large size parameters
AU - Yamada, Jun
AU - Kurosaki, Yasuo
PY - 1993
Y1 - 1993
N2 - Radiation transfer in fibrous media with large size parameters has been numerically investigatad using a pseudo-continuous model. In this study, first, we examine how the scattering from a single fiber can be approximated by the specular reflection on the fiber surface and the Fraunhofer diffraction of a rectangular aperture which is considered to be a single fiber. Considering the Fraunhofer diffraction and specular reflection, we derive approximate solutions for estimating the optical characteristics of fibers, such as extinction and scattering efficiencies, which are required in this model. By comparing the approximate solutions with the conventional exact solutions, it is shown that the approximate solutions are useful at size parameters of more than 50 and at absorption indexes of more than 0.1. Furthermore, with use of the optical characteristics obtained by the approximate solutions in combination with the conventional exact solutions, radiation transfer in two types of planar fibrous media with typical fiber orientations is estimated, and the effects of the optical constant of fibers, fiber diameter and the orientation on the radiation transfer in the media are presented.
AB - Radiation transfer in fibrous media with large size parameters has been numerically investigatad using a pseudo-continuous model. In this study, first, we examine how the scattering from a single fiber can be approximated by the specular reflection on the fiber surface and the Fraunhofer diffraction of a rectangular aperture which is considered to be a single fiber. Considering the Fraunhofer diffraction and specular reflection, we derive approximate solutions for estimating the optical characteristics of fibers, such as extinction and scattering efficiencies, which are required in this model. By comparing the approximate solutions with the conventional exact solutions, it is shown that the approximate solutions are useful at size parameters of more than 50 and at absorption indexes of more than 0.1. Furthermore, with use of the optical characteristics obtained by the approximate solutions in combination with the conventional exact solutions, radiation transfer in two types of planar fibrous media with typical fiber orientations is estimated, and the effects of the optical constant of fibers, fiber diameter and the orientation on the radiation transfer in the media are presented.
KW - Diffraction by Fiber
KW - Extinction Efficiency
KW - Fibrous Medium
KW - Large Size Parameter
KW - Scattering Efficiency
KW - Scattering by Fiber
KW - Thermal Radiation
KW - Thermophysical Properties
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U2 - 10.1299/kikaib.59.3187
DO - 10.1299/kikaib.59.3187
M3 - Article
AN - SCOPUS:0027685539
VL - 59
SP - 3187
EP - 3194
JO - Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B
JF - Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B
SN - 0387-5016
IS - 566
ER -