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Show o ~ 3 0.32 SPECTRAL FLAME RA.TlO DATA MIT TESTS G1 - ANALYZER MOVING AWAY FROM THE BURNER G2 - ANALYZER MOVING TOWARD THE BURNER METERS FROM BURNER FACE 1.02 Fig. 3 - Gas~Fired, 1 Percent Excess Oxygen Check for Self-Consistency 0.32 Fig. 4 G3 - ANALYZER MOVING AWAY FROM THE BURNER G4 - ANALYZER MOVING TOWARD THE BURNER SPECTRAL FLAME RATIO DATA MIT TESTS METERS FROM BURNER FACE 1.02 Gas-Fired, 3 Percent Excess Oxygen Check for Self-Consistency and 3 percent excess oxygen, respectively. These figures show the comparison of the results obtained when the SFA was moved away from the burner with the results obtained when the SFA was moved toward the burner. The data show consistency and as expected, close to the burner, the two sets of data are seen to be virtually identical for both the UV and IR channels. Both the IR and UV signals show valleys spaced at 0.3 m, corresponding to the location of the cold, water-cooled windows. These valleys are particularly pronounced for the tests carried out with gas-firing. Tests were performed by tilting the SFA to avoid the cold windows, while operating under identical conditions, i.e., 3 percent excess oxygen. The results are shown in Figure 5. The comparison clearly demonstrates that the valleys are, indeed, due to the effect of the water-cooled windows. Figures 6 and 7, respectively, show the variation in the OR and C02 response for 1 percent excess oxygen and 3 percent excess oxygen levels. Both the OR and C02 signals are very sensitive to the change in air-fuel ratio. 225 o G3 - ANALYZER MOVING AWAY FROM THE BURNER G5 - ANALYZER TILTED AND MOVING AWAY FROM THE BURNER ;:: 4 ~ SPECTRAL FLAME RATIO DATA MIT TESTS IRiREF G3 OL-__ L-__ L-__ L-__ L-~ __ ~ __ ~ __ ~ __ ~ __ ~ __ ~ __ -L __ -L __ ~ 0.32 0.42 0.52 0.82 0.72 0.82 1.02 • METERS FROM BURNER FACE Fig. 5 - Gas-Fired, 3 Percent Excess Oxygen, SFA Tilted to Avoid Cold Windows 3.5 3.0 2.5 0.42 0.52 SPECTRAL FLAME VOLTAGE DATA MIT TESTS - GAS OH SIGNAL 0.62 0.72 METERS FROM BURNER FACE 0.82 0.92 1.02 Fig. 6 - Plot of OR Species Versus Distance from the Burner for Two Excess Oxygen Levels 4.2 3.8 3.4 3.0 I/) ~ 2.6 0 > 2.2 1.8 1.4 1.0 0.32 0.42 0.52 SPECTRAL FLAME VOLTAGE DATA MIT TESTS - GAS CO, SIGNAL 0.62 0.72 0.82 METERS FROM BURNER FACE 0.92 1.02 Fig. 7 - Plot of CO 2 Species Versus Distance from the Burner for Two Excess Oxygen Levels |