Abstract
A study is presented on the operating characteristics of burners employing premixed, laminar flow air–acetylene and nitrous oxide–acetylene flames. The variables affecting flashback of these flames have been investigated and found to be critically dependent on such factors as burner port diameter, gas flow, fuel–oxidant ratio, and burner construction. Because the theory previously developed for stable flame formation on isothermal burners is not directly applicable to most burners used in flame spectrometry, an operational theory of flashback is developed. In accordance with this working model, safe limits of operation for conventional burners are examined and presented and important burner design criteria are established, including experimental quenching diameters for both circular port and slot-type burners.