Multipoint method for sample temperature measurement in a mirror furnace
Abstract
A multipoint method of obtaining an accurate sample surface temperature evaluation in a mirror furnace by performing pyrometric measurements at different wavelengths is proposed. The measurements are used to compute the unknowns in a set of equations describing the signals detected by the pyrometer, via the NewtonRaphson method. The solution is simplified by assuming that bulb and ampoule emissivity are independent of temperature and depend only on wavelength. Reflectivity of sample and ampoule is assumed to be constant. Success of the method depends on the initial guess for temperatures and the disturbance factors.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 June 1984
 Bibcode:
 1984STIN...8433789.
 Keywords:

 Computation;
 Image Furnaces;
 NewtonRaphson Method;
 Signal Processing;
 Temperature Measurement;
 Emissivity;
 Nonlinear Equations;
 Pyrometers;
 Temperature Effects;
 Wavelengths;
 Instrumentation and Photography