First spectral emissivity study of a solar selective coating in the 150–600°C temperature range

Importance of the spectral emissivity measurements at working temperature to determine the efficiency of a solar selective coating

“…(1) and (2), were found in a coating with double cermet layer of silicon oxide with different amounts of molybdenum over a silver infrared mirror layer [12]. The close agreement between the radiometric and reflectivity measurements in Fig.…”

“…Normal spectral emissivity is measured in each heating cycle at 15 different temperatures following the sequence shown in Ref. [12].…”

“…(1) and (2) is only accurate in the range of wavelengths where the emissivity spectra is measured with the radiometer (λ 1 rλrλ 2 ) and, it requires an approximation out of that range, that is in the ranges 0-λ 1 and λ 2 -1. However, if we now consider that most of the losses occur in the range (λ 1 rλrλ 2 ), the approximation is excellent [12].…”

“…at the working temperature [12]. A simple calculation shows that small differences between the ε T (T) values calculated by using Eqs.…”

Thermal emissivity spectra and structural phase transitions of the eutectic Mg-51%Zn alloy: A candidate for thermal energy storage

“…The analysis of the limits of integration and measurement errors were made elsewhere [30,31]. Figure ºC.…”