Home – Home – Jornals – Thermophysics and Aeromechanics 2020 number 3

The graph-analytical method (gray model) for estimating the true temperature of an opaque material from both above and below at the unknown character of emissivity dependence on the wavelength is presented. It is shown that if the diagram of spectral distribution of inverse radiance temperatures in the selected spectral range can be approximately represented by a line, convex downwards, then the obtained value of the spectral ratio temperature limits the true temperature from above. If the diagram of indicated dependence in the spectral interval can be represented by a line, convex upwards, then the obtained value of the spectral ratio temperature limits the true temperature from below. The solution to this inverse problem should be combined with the solution to the direct problem. As a result, additional information on the spectral distribution of the material emissivity in the selected spectral range appears. In addition, this is verification of the assumptions made. The paper also provides an example of processing experimental data known from publications.