Thermal radiative properties have significant influences on the radiative heat transfer process which be鄄
comes obvious in nanoinsulation materials at high temperature. In order to better understand the materials radiative
properties, a theoretical method based on Mie theories is presented for nanoinsulation materials containing both rein鄄
forcement fibers and opacifiers. Corresponding computer codes are developed and the thermal radiative properties are
studied theoretically for a specific nanoinsulation material. The parameters describing the radiative properties are ob鄄
tained which include the spectral extinction coefficient and scattering albedo, the Rosseland averaged extinction coeffi鄄
cient and scattering albedo, the Rosseland averaged scattering phase function etc. Results from theoretical simulation in鄄
dicate that for the wavelength studied between 3 滋m and 9.5 滋m,the material has strength extinction to thermal radia鄄
tion. The material exhibits highly scattering for thermal radiation with the wavelength between 3 滋m and 7 滋m. For
thermal radiation with the wavelength between 7 滋m and 9.5 滋m, the scattering phenomenon becomes weak with the in鄄
crease of wavelength. For thermal radiation with the wavelength of 9郾5 滋m, the material exhibits obviously absorbing.
Under the temperature between 300 K and 1 300 K,the rosseland averaged extinction coefficient of the nanoinsulation
material is greater than 50 000 m-1,and its averaged scattering albedo is greater than 0.96. The highly forward scattering
characteristic of the material results from the opacifier and the reinforcement fibers in the material have less influences.