Flame Stabilization and Emissions of a Natural Gas/Air Ceramic Porous Burner

Abstract

Increasingly stringent regulations for limiting pollutant emissions for both aircraft and industrial gas turbines enforce further reduction of NOx emissions while maintaining flame stability. Application of premixed flames offers the possibility to reduce these emissions, but nevertheless it is strongly connected with flame instability risks. A possible solution to ensure the stability of premixed flames is to provide enhanced heat recirculation employing porous inert material. Experimental determination of flame stability and emissions of a porous burner containing a reticulate ceramic sponge structure are reported and the influence of the structural properties of the porous matrix on stable operating range was investigated. It was found, that the flame stability limit was significantly higher compared with free flame burners and nitric oxide (NOx) emissions were below 10 ppm for all cases.