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Show ~ " ~ '4 ~ .. I' I' j, '4 "' ~ ~ :D. ~ ~ ~ ~ • ~ ~ ~ • - , ~ • - - - - - - - - - - - - - - - - I Secondary • • • .. ... _--- - - - - - - - - - - I Jet ~ - --------- - - - - - - - - - - - " ~ ~ ~ • - - - - - - - - -" - - - - - - v v v v v " ~ ~ • - -" - - - - - • • ... - v .. '4 .. .. " • ., .", .I ., - r r p p 'r • • • I " "' " .. " - ....- ....- .I - ., ., -I -I .. A .f 'r • • I I " ,., -' - -I ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ • I Primary .I , ., " ~ ~ ~ c ~ ~ ~ c ~ ~ • ~ Inlet ., " ~ ~ ~ c ~ ~ c ~ c " ~ ~ ., • 2om/s~ " ~ I' • c A I ~ 20m/s I Tertiary Inlet I ~~ Furnace Wall Figure 14. In-flame velocity and direction 'Vector" plots for the baseline flame condition. The plots show data taken on a plane extending axially and radially through the secondary jet path. SUMMARY AND CONCLUSIONS The wide variety of diagnostics available at the BERL allow detailed investigation of in-flame burner characteristics. The results can be used to bolster present understanding of combustion principles as well as to identify special characteristics of a burner which were previously unknown. This burner study was useful in identifying the combustion and mixing regions and the relative impacts of process changes on these regions. In conclusion, the greatest effect on NOx emissions resulted from secondary jet fuel dilution with gases such as air and nitrogen. By use of inflame velocity data, planar Mie scattering jet mixing images, chemiluminescence ·CH radical concentration images and in-flame gas composition and temperature data, the impacts of burner process changes can be better understood. The data collected in this study have been and will continue to be valuable in the understanding of the NOx perfonnance of the Selas K988 burner. The results are also likely to be extensible to general understanding of modes for designing future gas burners with low NOx emissions. REFERENCES I. Phil Zahodiakin. "The Clean Air Act of 1990" Business Publishers, Inc. 1991. 2. C.F. Edwards and PJ. Goix. "Effect of Fuel Gas Composition and Excess Air on VOC Emissions and Flame Structure of a Small-Scale Industrial Burner." Presented at: The Fourth International Congress on Toxic Combustion Byproducts. Berkeley, California. June, 1995. 3. "Implementation Strategy for the Clean Air Act Amendments of 1990 (Update, 1992}." U.S. Environmental Protection Agency, Office of Air and Radiation. July 24, 1992. 13 |
