Spectral radiative property measurement and identification of two kinds of insulation material at high temperature

Accurately obtaining the thermal radiation properties of strongly scattering and extinction materials can promote efficient energy utilization and indirectly ensure low-carbon environmental protection. In order to investigate the temperature dependence of the radiation properties of insulation ceramics and fiber insulation materials, a high-temperature bidirectional transmittance and reflectance measurement device was designed. A radiative transfer model was established using Monte Carlo method, and a discrete scattering phase function was proposed to accurately describe its scattering characteristics. The experimental setup was initially subjected to heat analysis and stray light influence study to guarantee experiment accuracy. This type of strong extinction material can ensure temperature uniformity when the thickness is less than 2 mm. In high-temperature experiments, when the temperature is above 800 °C and the detector angle is below 10°, the measurement signal will be affected by stray light. This work inverts the radiation properties of two materials and suggests a new discrete phase function to derive the radiation properties of participatory media. Among them, thermal insulation ceramics exhibit high extinction, and their scattering characteristics show significant scattering within 10° deviation from the normal direction. Significant scattering is seen in fiber insulation materials within a 20° normal deviation range.