INNOVATIVE FUEL INJECTOR/FLAMEHOLDER CONCEPT FOR RAMBURNERS

RECENT STUDIES OF TURBORAMJET PROPULSION SYSTEMS HAVE IDENTIFIED THE NEED OF ADVANCED, INSTREAM FUEL INJECTION/FLAMEHOLDER SCHEMES FOR RAMBURNERS. THIS PROJECT PROPOSES TO DEVELOP A NEW, CLOSE-COUPLED FUEL INJECTOR/FLAMEHOLDER CONCEPT WHOSE DISTINGUISHING CHARACTERISTIC IS A CORRUGATED FLAMEHOLDER SURFACE. AS COMPARED TO A CONVENTIONAL INTEGRAL FUEL INJECTOR/FLAMEHOLDER (IFF) CONCEPT, THE NEW CONCEPT WILL HAVE THE FOLLOWING ADVANTAGES: 1. ENHANCED MIXING/CHEMICAL EFFICIENCY DUE TO INCREASED AXIAL VORTICITY; 2. LOWER PRESSURE LOSS DUE TO REDUCED FLAMEHOLDER BASE BLOCKAGE; 3. WIDER BLOWOUT FUEL/AIR LIMITS DUE TO DUAL-SIZE INJECTION ORIFICES; AND 4. SUPPRESSION OF COMBUSTION INSTABILITY DUE TO VARIABLE FLAMEHOLDER WIDTH. IN PHASE I, BOTH CONVENTIONAL AND ADVANCED CONCEPTS WILL BE NUMERICALLY ANALYZED USING A VALIDATED, 3D BODY-FITTED COORDINATE CFD CODE. TURBULENT, GASEOUS COMBUSTION SIMULATIONS WILL BE USED TO ASSESS AND SHOW THE FEASIBILITY OF THE ADVANCED CONCEPT. IN ORDER TO GAIN CONFIDENCE IN THE SIMULATIONS, THE IFF CALCULATIONS WILL FIRST BE VALIDATED AGAINST RECENT EXPERIMENTAL DATA FROM UNITED TECHNOLOGIES RESEARCH CENTER. IN PHASE II, AFTER PARAMETRIC CFD STUDIES FOR OPTIMIZATION, THE ADVANCED CONCEPT WILL BE DESIGNED, FABRICATED AND TESTED IN A RAMBURNER COMPONENT TEST RIG AT UNITED TECHNOLOGIES CHEMICAL SYSTEMS DIVISION OR SUITABLE TEST VENDOR. IF SUCCESSFULLY DEMONSTRATED, THE ADVANCED CONCEPT WILL BE TESTED AND EVALUATED IN A TURBORAMJET ENGINE DEMONSTRATOR IN PHASE III.