Determination of the hot gas concentration from the difference between contact and remote measurements of the temperature

A method of determining small concentration of hot gases from the difference between indications of sensors whose operation principles are based on contact and remote methods of measuring the temperature of a gas volume is suggested in the paper. It is assumed that the contact measurements allow the true kinetic gas temperature to be determined, and the remote pyrometric measurements yield the radiant temperature. The temperature difference depends unambiguously on the gas concentration, and for the proper chosen working spectral ranges corresponding to concrete requirements, the numerical value of the concentration can be found.