Next generation aircraft propulsion systems inevitably place higher thermal loads on jet fuel since it is used as primary heat sink for engine, hydraulics, avionics and other on-board systems. Increased fuel temperatures prior to combustion may lead to deposit formation in fuel systems and combustion sections. This limits engine performance, puts a burden on maintenance personnel and increases operational costs. U.S. Air Force, industry and academia therefore decided to team up and start the development of thermally stable fuels in the late eighties. This initiative eventually led to the formulation of an additive package capable of improving fuel thermal stability with 100°F (56°C). Although significant experience has been gained with the additive in military applications, the potential in the much larger civil market is yet untapped. Recent evidence however indicates the ability of the additive to reduce particulate emissions and component wear as well. This paper describes the experiments that were undertaken with a stationary gas turbine located at Delft University of Technology (DUT). The proprietary additive in question, provided by Shell Aviation (SAV), was added to commercial Jet A-1 kerosene. Repeatable tests were conducted to characterize the exhaust aerosol and combustor deterioration of the test-rig with standard and dosed fuel. The outcome of the experiments indeed suggests a role of the stability additive in soot (precursor) formation processes. Short-term cleaning effects inside the combustor were not observed however.

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