Designing a Laboratory Stand for Determining Coatings Emissivity

In this paper, the theory of heat transfer by radiation and the technique for measuring coatings emissivity are reviewed. Two variations on experimental installations while heating the studied surface, with both water and steam, are proposed. An experimental stand was created by heating with hot water at atmospheric pressure. The emissivity of polished oxidized aluminum and candle soot was measured. Measurement results are compared with the results obtained by other authors. Conclusions about the advantages and disadvantages of the created stand were drawn. During the testing measurements, the presence of a characteristic dependence of the emissivity on the radiation angle was confirmed, the maximum of which for aluminum occurring at angles close to 75-85°.