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Show insulating board. Initial tests included six radial traverses at 27, 109, 177, 191, 343, and 432 nun downstream of the burner throat. A probe was inserted into the furnace, and sufficient data were collected to quantify the internal reaction zone (lRZ), reaction zone, and external reaction zone (ERZ). For the radial profiles, the collection density of data is greatest in the IRZ (-10-15pts.) and reaction zone (-10-15pts.) and least in the ERZ « 10pts.). A cold-wall set of measurements was also taken, but these are not discussed herein. The furnace inlet flow conditions are listed in Table 1, while Table 2 contains wall conditions for the furnace. The geometry of the gas burner is schematically shown in Figure 2. The 300kW burner used in the measurements is a swirl-stabilized natural gas (NG) burner of the same type used in the SCALING 400 study (Sayre, et al., 1994) at the BERL facility. The 300kW burner is circumferentially symmetric with a bluff centerbody containing 24 radial natural gas injection holes. A NG fuel analysis is listed in Table 3. Combustion air is introduced through one annular zone and swirled using IFRF swirl blocks. Although the burner is capable of providing flue gas recirculation (FGR) or NG staging, neither is considered. Data collected by Sayre and others were judged of good quality and were used as the baseline set. Additional measurements were recommended and collected recently (Kaufman and Fiveland, 1995). A set of non-reacting flow measurements were collected to verify the flow and turbulence model. More in-flame measurements were collected to better quantify the flame and the region downstream for 11 additional traverses at 0, 16, 65, 131, 150, 208, 390, 510, 695, 815, and 1156mm for non-reacting and reacting flow conditions. For the nonreacting conditions, laser doppler velocimetry measurements were made for the u- and wcomponents of velocity. For the natural combustion tests, in-furnace probing was completed for velocity (u- and w-components), temperature, and major species including O2, CO, CO2 , H20 and unburned hydrocarbons. RESULTS The physical domain was modeled with several 2-D computational grids: a coarse base grid of 7130 control volumes, a fine base grid with 14,600 control volumes, and three additional grids (18,900, 27,700, and 47,600 control volumes), with improved resolution 5 |
