The principle and analysis of accuracy of a two-color-emission-CT pyrometer

An algorithm of a two-color-emission-CT (computed tomography) pyrometer is presented, and the measured values of temperature and density of burnt gases are discussed. The greatest advantage of this method is that it needs no blackbody as a reference source and only one window for each light path. A CT algorithm using gases and small particles as the radiators and the dependence of accuracy on the wavelength are discussed theoretically. It is concluded that the self-absorption effects can be compensated and the density distributions of radiation-active components can be obtained. The CT method makes it possible to measure both temperature and density distributions of high-temperature gases without an intrusive sensor. Experimental results for several flames are presented and discussed