Device for measuring the surface temperature and emissivity of a object heated in an oven

摘要

Described is a device comprising a black-body radiator for emitting temperature radiation (thermal radiation) towards a particular point of the surface of an object heated in an oven, and further comprising a radiation detector for measuring the radiation coming from that particular point. A first measurement relates to the radiation coming only from the object. A second measurement relates to the radiation coming directly from the object combined with the radiation coming from the black-body radiator and reflected by the object towards the radiation detector. Also measured is the temperature of the oven wall. The measurement data are used for an accurate calculation of the surface temperature T1 and the emissivity ε(θ) of the object, even in the case where the object has an imperfectly reflective surface, by introducing a diffuse-reflection factor p. <IMAGE>