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Show Figure 3 shows the resulting set of mass breakthrough fractions for a typical model run. By definition, all of the waste escapes the flame region. At high centerline temperatures, essentially all ("ten nines") of the waste is destroyed. (In fact, thermodynamic equilibrium probably limits the destruction long before this point.) However, only 98.1 percent of the waste material which travels in the annul us nearest the wall is destroyed. Algorithms The algorithms used to calculate the various heat and mass flow values are mostly of a standard form. A control volume is drawn around each zone and the energy flows summed and set equal to zero. Separate flows are considered for heat losses to water-cooled combustor surfaces and refractory (insulating brick) surface. Zone Heat Balance Figure 4(a) shows the simplest formulation of the control volume heat balance, Case I, in which wall heat losses are accounted for by seven heat fluxes: rad WW rad ref Radiative transfer from zone to adjacent waterwall surfaces Radiative transfer from zone to adjacent refractory wall surfaces Volume flow percent 95 percent , I, Near flame J 7 j-6 J-5 J'4 J'3 i'2 j*l Haste: Dichlorobenzene Exces-s air: 25 percent Firing rate: 0.8 Billion Btu/hr Run 19 Annul): 0, 1/8, 1/4 radius Figure 3. Sample Boundary Layer Module Prediction of Axisymmetric Mass Breakthrough Fractions 5.5.4 |