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Show FLUE GAS ~ POROUS BURNER +----tl r------f1~ RECORDER ~ NA TU RAL GAS r SSI • ,') e-If'" Figure 2. Schematic diagr~f the experimental setup. material on flame stabilization, ~_~~esent studies were conducted using different types of ceramic foams, honeycomb plates, and particles made of alumina (A1203), zirconia (Zi02'), and silicon carbide (SiC). Different types of radiating surfaces wi th and wi thout coatings were also used to evaluate the effect of surface emissivity on radiation heat output. The total depth of the porous bed is 4 inches. The entire burner unit is well insulated by zirconia fiber to minimize heat loss. DATA COLLECTION The combustion rate, stoichiometric ratio of air/fuel, exhaust gas temperature and composition, and pressure drop across the unit were measured for regular diagnostics of performance of the test porouscombustion radiant burner. The flow rate of natural gas was measured using a rotameter and a positive-displacement natural gas meter, whereas the combustion air flow, drawn from the laboratory at ambient temperatures, was monitored with a rotameter. The static pressure of the gas/air mixture was measured by a pressure gauge located in the inlet plenum. This pressure represents a pressure drop across the mixture distribution grate and the porous matrix bed. |