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Show Since the contributions from each of these regions to the total EINOx level in the flue gases are essentially independent, the overall NOx emissions index is given as EINO MWN02 X flue = . mfuel + + + { [ d[NOX] . v] dt near-burner [ d[NOX] . V] dt flame-sheet [d[:~xj . V] furnace [ d[NOX] . V] } dt ., stagmg-Jet Substituting (4) into (5), the scaling model for overall NOx emission becomes EI NOxflue = M.WN02 . 1.45 X 1017 mfuel . {[T-1 / 2 exp[ -69460/Tj· [02j!t2[N2jeq . VL.r-burn" + [T- 1 /2 exp[ -69460 /T] . [02]!q/2[ N2]eq . V] flame-~heet + [T- 1 /2 exp[-69460/T] . [02]!q/2[N2]eq . V] furnace (5) + [T- 1 / 2exp[-69460/T]. [02]!t2[N2]eq' V] . . } (6) 3tagmg-Jet The NOx output is then determined by the volume V, temperature T, and [02 ] and [N2] concentrations of each of these regions. The following subsections examine how each of these four factors scale in each of the four NO producing regions. 4.1 Volullle Scaling 4.1.1 V in Near-Burner Region The near-burner region is composed of the burner recirculation zone and the adjacent high temperature region. As shown in Fig. lOb, the resulting volume is simply wi th V'i and V2 scaling as Vnear-burner = V'i + V2 a1 .110: a2 . 120~ (7) (8) For simplicity the shapes are approximated by cylinders, thus giving the proportionality constant al,2 = 7r. Assuming perfect aerodynamic similarity, the dimensions of the nearburner region scale with burner size Do in Table 1 as 11 ,2 b1,2 . Do 01;2 C1,2 . Do (9) 8 |