Abstract:
An integral emissivity (e.g. a degree of blackness,) is the most important characteristic that determines the intensity of a heat transfer by radiation. In a process of a various heat and power plants design, thermal protection for spacecraft, etc. one needs to know a temperature dependence of the degree of blackness $\epsilon(T)$ of the materials used. At present, a growing demand for the new structural and composite materials with specified characteristics and a controlled degree of blackness, are investigated and used. This paper presents a methodology for the degree of blackness definition of porous materials with low heat capacity. This methodology assists in a calculation of the temperature dependence of the ceramic composite material VMK-5 $\epsilon(T) = 0,0002867T + 0,114$.
Keywords:degree of blackness, reflection coefficient, transmittance, cooling curve, composite material, heat capacity, integral emissivity, composite ceramic material, thermo radiometer.