New Spectrophotometer System for Measuring Thermal Radiation Characteristics of Real Surfaces of Thermal Engineering Entirely

Abstract

In this work we develop a new spectrophotometer system for measuring thermal radiation characteristics of real surfaces of thermal engineering. This system measures transition of spectra of normal incidence hemispherical reflectance RNH, normal incidence specular reflectance RNN, normal incidence diffuse reflectance RND, normal incidence absorptance AN and normal emittance εN of real surfaces in a near-ultraviolet through infrared region of wavelength 0.30∼11 µm simultaneously and repeatedly with a cycle time of 6 s. The system is applied to measure the spectrum transition of the reflectances, absorptance and emittance of a nickel surface which is prepared as a clean optically smooth surface and is oxidized in high-temperature air to be changed to an oxidized rough real surface. Microscopic mechanisms of the spectrum transition are discussed, to illustrate the performance of the developed spectrophotometer system for thermal engineering applications.