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

Abstract

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.

Recent development in studies of alternative jet fuel combustion: Progress, challenges, and opportunities

“…While the lean blowout tests of [58,68] showed no significant differences between the tested alternative jet fuels and conventional ones, the results of [59] demonstrated a better LBO performance for the tested FT CTL than RP-3 at low liner pressure drop conditions, which could be caused by the different fuel distillation curves as suggested by the authors. Burger et al [69] has systematically studied the lean blowout behavior of Sasol FSJF ® , SPK, Jet A-1, and other fuel blends in a heterogeneous laboratory combustor.…”

“…The results of [65] showed that CO emission index for SPK was higher than that for Jet A-1 in the leaner conditions and was lower in the richer conditions; and NO x emission index for SPK was lower than that for Jet A-1 in all the tested conditions, except for rich conditions at high inlet air temperatures. Shouse et al [68] compared the emissions of a FT GTL with those of JP-8 and found that CO emission of GTL was lower than that of JP-8 for all the tested F/A, while NO x emission of GTL was lower than that of JP-8 at leaner conditions, but higher at richer conditions. Other tests of [59,71] showed no significant differences in CO and NO x emissions between the tested alternative and conventional jet fuels.…”

“…Although differences are observed, the emissions of CO and NO x are generally in the same levels for both alternative and conventional jet fuels; the major difference in emissions with alternative jet fuels is in soot emission. In particular, the combustor emission tests of [65,68,[70][71][72] all showed significant reductions in soot (smoke) emission when using alternative jet fuels. For example, Pucher et al [71] showed that a 100% GTL and a 50/50 GTL/Jet A-1 blend had 83% and 65% reductions in smoke emission, respectively, compared to the base Jet A-1 fuel; and a 100% HRJ had 96% reduction in smoke emission.…”