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Show spectra for the experimental arrangement as a function of temperature and match these spectra to the measured spectra, inferring the temperature from the best fit. This technique also allows any anomalies in the experimental spectra to be readily identified. II. Test Facility and Gas Stream Characteristics The combustor operates in an insulated test stand and is controlled and monitored by computer. It is designed to simulate the conditions found in the post-magnet gas stream of a coal-fired MHD power plant. Air at 1.1 atm pressure and at a flow rate of 228 kg/hr is preheated to ~1000K by electrical resistance heaters and used to oxidize fuel oil (diesel //l) in a combustor to obtain a nominal temperature of 2500K. Flyash (residues of coal combustion) and seed (K2SO4) can be injected into this hot gas stream at maximum rates corresponding to 100 percent flyash carryover and 1 percent potassium mass concentration. Fuel flow can be adjusted to provide air/fuel stoichiometric rates between 0.8 and 1.2. For versatility, the test stand is assembled in sections. These sections, available in 20.5 cm (1 ft), 61 cm (2 ft) and 122 cm (4 ft) lengths, allow optical access to the gas stream via ports along their length. Three types of sections, classified by insulation, are used: 10 cm thick refractory lined, 2.5 cm thick refractory lined and bare-walled stainless steel. Each of these has an inner diameter of 20.3 cm and and outer diameter that is water cooled. Calorimetric calculations based on the temperature of this cooling water allow estimates of average gas temperature along the flow to be made. Slag or an 8:1 (by weight) mixture of seed and slag can be fed into the combustor from holding tanks located one floor above the test stand. These powders are auger driven from pressurized tanks and fed into the combustor air supply. Injection rates are changed by adjusting the auger speed. After a few hours of injecting flyash, the interior walls of these test stand sections accumulate a slag coating which modifies their thermal characteristics. A more complete description of the test stand and its operation is available elsewhere (19) as is a predictive thermal model for the facility (20). 5 |