Abstract

The results of techniques developed and used to determine the mean effective emissivity of different surfaces over a range of temperatures from 100 to 800 F are presented. The measurement of radiant energy from the surfaces is accomplished by means of a 160-junction silver-constantan directional thermopile radiometer. Serious errors are noted and accounted for when improper use is made of polished shields in the experimental arrangements. This represents a refinement over previous techniques used; further refinements are anticipated with the ultimate aim of checking against integrated spectral data. However, the data presented are useful aids as a phase of the technique of evaluation of equilibrium temperatures of different surfaces exposed to solar irradiation.

This content is only available via PDF.
You do not currently have access to this content.