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Show Fig. 8 - Flow Vlsual1zatlon Results for Swirl Burner Flow Model 1-- r= f. O[~!G ~ 8 Fig. 9 - Velocity Prof1le Test Results for High Swirl Coal Nozzle 124 LARGE SCALE TANGENTIAL FIRED FURNACES - Combustion Engineering as the manufacturer of Tangentially- Fired furnaces, is committed to confinually optimize the performance of these boUers. As described earl1er, the center of this effort, 1n terms of furnace aerodynamics 1s the recently constructed Large Scale Furnace Aerodynamics Test Facllity ([SFATF). A number of isothermal furnace flow model studies have been performed at this facllity and considered such furnace operating parameters as fuel-air mixing, overf1re air injection performance, and 1njection of sulfur capture sorbents into the upper furnace. Because pulverized coal combust lon, slmllar to other fuels, is limited by the fuel-alr mixlng process, a recent test program was performed at the LSFATF to investigate methods of enhanclng fuel-air mlxlng. The ob1ectlve of this program was to design a Mretrofftable" firing system to enhance fuel-air mlxing while mlnim1zing potentlal increases to lower furnace slagglng and bol1er tube eroslon. A number of the fumace modeltng 1nstrumentation techn1ques descr1bed earHer were utilized. Three dimensional velocity traverses us1ng a five hole p1tot tube and the Automatic Probe Traversing Device provided detal1ed three dimens10nal cnaracterizat10ns of the velocity flow fields wlth1n the model. As fuel-air m1x1ng was of pr1mary interest, a laser absorption spectrophotometer was used to determine the stotciometry at various locations in the unit. Variables investigated included fuel and a1r fir1ng angle, aux111ary air velocity, overfire air flow, and fumace load. Flow visuallzation techniques ut111z1ng smOKe and yam streamers were also used to characterize the combustion zone aero~nam1cs and to provide a view of the overall furnace flow patterns. Typ1cal results from one of the flow visual1zation tests are shown in Figure 10. F1g. 10 - Typical Results - Flow V1suaJ1zatlon Tests |