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Show DEVELOPMENT OF A GENERALIZED BURNER DESIGN PROCEDURE AFRC90 Paper #26 Steven J. Bortz 5) r k \ R-C Environmental Services & Technologies Irvine, California 92718 and Shyh-Ching Yang Energy & Resources Laboratories/Industrial Technology Research Institute, Hsinchu, Taiwan, R.O.C. ABSTRACT A genera 1 i zed burner des i gn procedure has been formu 1 ated us i ng empi ri ca 1 and semi-empirical correlations for fuel burnout, ignition behavior and NOx emi ss ions as a funct i on of the burner inputs, burner geometry and swi r1 levels. The procedure has been used to design a dual fuel gas/oil low NOx burner which was consequently constructed and tested in the ERL combustion test faci 1 i ty. The measured burner performance was near the predi cted performance for all the design values, with a 5/1 turndown and NOx emissions of less than 30 ppm on gas and 100 ppm on oil being achieved. INTRODUCTION When a burner is designed to meet a particular goal, whether it be controlling combustion stability, flame shape, pollutant emissions, or other criteria, the design normally entails two steps. Firstly the appropriate input levels and mixing rates of fuel, air, and recirculation gases required to obtain the desired performance must be selected, and then the burner must be designed to achieve that mixing rate. Swirl in one or more of the burner fluid streams is often utilized in industrial burners to achieve the desired ignition, flame geometry and burnout characteristics for a given fuel. Swirl can be a particularly effective method of controlling a flame, since the ignition behavior can be improved by changing the internally recirculated mass flow rate, and the fuel/air mixing rate can be regulated by altering either the swirl level and/or burner geometry (see Figure 1). A 1 though the genera 1 i nfl uence of swi rl 1 eve 1, burner and furnace geometries on the flow field near the burner (the near field) are to some -1- |