Gas turbine combustor and engine augmentor tube sooting characteristics

Abstract

An experimental investigation was conducted to investigate the effects of smoke-suppressant fuel additives, fuel composition and combustor operating environment on the soot characteristics within the combustor and across an engine exhaust augmentor tube. A T63 combustor was used with fuel additive pumps and an exhaust augmentor tube. Soot mean diameters and concentrations were measured at two locations within the combustor and at the exhaust of the augmentor tube using three-wavelength light transmission and multiple-angle forward scattering measurements and collection probes. Fuel and air flow rates were varied and combustor inlet air temperature was varied using a hydrogen-fueled vitiated air heater. Combustor flow conditions were found to significantly change soot characteristics as well as the effects of smoke- suppressant fuel additives. D32(volume-to-surface mean diameter) varied between 0.10 and 0.30 microns within the combustor. D32 increased significantly across the engine augmentor tube, to sizes as large as 0.43 microns