Estimation of the effect of the blackness coefficient on the error in determining the emissivity of materials

The article considers the influence of the blackness coefficient on the emissivity of various materials. Determining the precise values of the thermal conductivity and heat exchange is of crucial importance to solve problems of power supply and to ensure optimal temperature conditions of premises since the choice of materials for the manufacture of various buildings, structures and their structural elements depends on the heat exchange. The emissivity of materials, in particular, the values of the blackness coefficients in the calculation of radiation heat exchange plays a significant role in the formation of the thermal balance. The contribution to the total heat exchange from radiation processes can be significant and vary significantly for different temperature conditions. This study demonstrates that the error in estimating the radiative heat flux depends on the type of spectral characteristic of its emissivity, and the use of the integral blackness coefficient can significantly increase the error in determining the heat flow from the surface of objects, including construction materials. (paper)