Alternate-Fueled Combustor-Sector Performance—Part A: Combustor Performance and Part B: Combustor Emissions

Alternate aviation fuels for military or commercial use are required to satisfy MIL-DTL-83133F or ASTM D 7566 standards, respectively, and are classified as “drop-in’’ fuel replacements. To satisfy legacy issues, blends to 50% alternate fuel with petroleum fuels are acceptable. Adherence to alternate fuels and fuel blends requires “smart fueling systems’’ or advanced fuel-flexible systems, including combustors and engines, without significant sacrifice in performance or emissions requirements. This paper provides preliminary performance and emissions and particulates combustor sector data. The data are for nominal inlet conditions at 225 psia and 800°F (1.551？MPa and 700？K), for synthetic-paraffinic-kerosene- (SPK-) type (Fisher-Tropsch (FT)) fuel and blends with JP-8+100 relative to JP-8+100 as baseline fueling. Assessments are made of the change in combustor efficiency, wall temperatures, emissions, and luminosity with SPK of 0%, 50%, and 100% fueling composition at 3% combustor pressure drop. The performance results (Part A) indicate no quantifiable differences in combustor efficiency, a general trend to lower liner and higher core flow temperatures with increased FT fuel blends. In general, emissions data (Part B) show little differences, but, with percent increase in FT-SPK-type fueling, particulate emissions and wall temperatures are less than with baseline JP-8. High-speed photography. 1. Introduction Synthetic and biomass fueling are now considered as near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. Alternate aviation fuels are currently required to satisfy MIL-DTL-83133F for Fisher-Tropsch- (FT-) equivalent processed ASTM D 7566 and known as “drop-in” fuel replacements (military and civil, resp.). As in aviation, many land-based and marine power generation systems are elderly, known as the legacy issue. Fueling these systems requires careful compliance to the fuel handling and engine systems for which they were (are) designed. To satisfy a sustainable fuel supply, it will be necessary to accept fuels derived from a variety of feedstocks. Consequently, adherence to alternate fuels and fuel blends requires “smart fueling systems” or advanced fuel-flexible systems, including combustors and engines, without significant sacrifice in performance or emissions requirements. The common military services fueling concept is that JP-8+100 or alternate FT-type fuels that can fuel gas turbines as well as many diesel systems. Diesel biomass-derived oils are often unsuitable because