Abstract
This paper describes the radiation effect on the NOx emission of confined nonpremixed flames. The characteristics of confined flames are strongly affected by the entrainment of burned gases. The burned gases have two factors; one is dilution and the other is heating. Proper combination between geometries of burner and furnace can reduce the NOx emission. The radiation effect on the NOx reduction has been investigated by comparing NOx emissions from two furnaces with Pyrex glass and stainless furnace walls. It was found that the radiation fraction has a logarithmic relation to the product of global equivalence ratio and flame volume.
