THERMAL STABILITY OF AVIATION FUELS

THE EFFICIENT DEVELOPMENT OF ADVANCED AIRCRAFT CONCEPTS OR INTRODUCTION OF NEW FUELS WILL REQUIRE INCREASED MECHANISTIC UNDERSTANDING AND MODELS TO PREDICT THERMAL STABILITY IN ORDER TO ELIMINATE THE REQUIREMENT FOR EXTENSIVE EMPIRICAL TESTING. THE PROPOSAL IS FOR A COMBINED EXPERIMENTAL, ANALYTICAL, AND MODELING PROGRAM TO DEVELOP A MECHANISTIC UNDERSTANDING AND MODEL OF FUEL THERMAL STABILITY. THE PRIMARY OBJECTIVE OF THE PROGRAM CARRIED THROUGH PHASE II IS THE ABILITY TO PREDICT, GIVEN THE COMPOSITION OF THE FUEL AND THE CONDITIONS IN THE FUEL LINES AND ENGINE, THE DECOMPOSITION OF THE LIQUID, THE FORMATION OF GUMS IN THE LIQUID AND THE DEPOSITION OF SURFACES. IN ADDITION, WE EXPECT THAT AN ON-BOARD FUEL STABILITY MONITOR CAN BE DEVELOPED BASED ON A PORTABLE FT-IR INSTRUMENT AND A SPECIALLY CONSTRUCTED CELL. THE PROGRAM WOULD UTILIZE SPECIALIZED ANALYTICAL TECHNIQUES FOR HYDROCARBON FUELS THAT HAVE BEEN DEVELOPED AT ADVANCED FUEL RESEARCH, (AFR), INC. AND SRI INTERNATIONAL (A SUBCONTRACTOR). IT WOULD ALSO EMPLOY SEVERAL MODELING TECHNIQUES FOR HYDROCARBON THERMAL DEGRADATION, WHICH HAVE BEEN DEVELOPED AT AFR. THE OBJECTIVE OF THE PHASE I PROGRAM IS TO DEMONSTRATE THE VALUE OF THESE SPECIALIZED ANALYTICAL AND MODELING TECHNIQUES DEVELOPED AT AFR AND SRI FOR FOLLOWING THE PROGRESS OF FUEL THERMAL DEGRADATION. IN PHASE II, A WIDER RANGE OF FUELS AND CONDITIONS WOULD BE INVESTIGATED AND THE DETAILED MODEL DEVELOPMENT AND VALIDATION WOULD OCCUR. THE PHASE II EFFORT WOULD ALSO INCLUDE FURTHER DEVELOPMENT OF THE ON-BOARD FT-IR DIAGNOSTIC INSTRUMENT.