Book Description

An exploratory development program was conducted to identify, evaluate, and demonstrate improved combustion design techniques for increasing combustion efficiency at part-power operating conditions, thereby reducing undesirable and potentially hazardous exhaust emissions. The most promising of the low-power design techniques investigated, fuel-air premixing and virtual staging, were incorporated into an annular burner configuration and a detailed experimental evaluation of the combustion system was accomplished. The burner was examined at both low-power and simulated design-point operating conditions. Relative to the part-power goals that served as guidelines for the demonstration hardware, viz. a Smoke Number less than 20, carbon monoxide concentration of 10 ppmw, total unburned hydrocarbon concentration of 10 ppmw, and combustion efficiency greater than 98%, those relating to smoke, hydrocarbon concentration, and efficiency were exceeded; that relating to carbon monoxide concentration was approached. A detailed, computerized, theoretical model developed earlier in the program to predict the emission characteristics of combustion systems at part power was used to support the demonstration burner program. (Modified author abstract).