| OCR Text |
Show exhaust temperature of the combustion products, and a sixth thermocouple records ambient temperatures. These thermocouples are all interfaced with the computer. Emission analysis of the combustion products is conducted with a chemilumenescent NO-N02-NOx analyzer, an infrared CO analyzer, and a 02 process monitor. Samples are taken 4 cm (1.5") above the fin-and-tube heat exchanger as the product gas enters the chimney. TEST PROCEDURE & DATA ANALYSIS The thermal efficiency and emissions were determined by varying a) equivalence ratios from 0.60 < $ <0.95; b) input power levels between 12 to 18 kW (40,000 to 60,000 Btu/h); and c) water flow rates from 8 to 30 liters/min (2 to 8 gal/min). The test matrix has three different power input levels. F or each power level, while keeping the water flow rate at 16 liters/min, $ was adjusted from 0.65 to 0.9 in steps of approximately ~<l> =0.05. Swirl air was adjusted as necessary to stabilize the flame. A second series was conducted with $ held constant while the water flow rate adjusted from 8 to 30 liters/min (2 to 8 gal/min) in steps of 4 liters/min (1 gal/min). After setting the water flow rate and waiting for the water temperatures to reach steady-state (usually within one minute), the computer recorded gas and air flow rates, 4>, temperatures, thermal efficiency, and NO/CO/02 concentrations every three seconds and refreshed the readings on the video display. Each run lasted for ten minutes. Thermal efficiency, E, for this system is defined as E = mfCp~ Tw = Energy transferred to water mr * I-ll-IV Chemical energy entering with fuel (2) with mw and mf referring to the mass flow rates of water and fuel respectively, cp the specific heat of water, HHV the high heating value of the fuel, and IlTw the difference between the water temperature exiting and entering the heat exchanger. For this analysis, cp and HHV were assumed to be constant at 4.18 kJ/kg/K (0.998 Btu/Ibm/oF) and 38,400 kJ/m3 (1030 Btulft3 ) respectively. It should be noted that this is neither a combustion nor 7 |
