DEVELOPMENT OF A PYROPHORIC FUEL THRUST AUGMENTER FOR THE J69 ENGINE 600406
Continental Aviation and Engineering Corporation has developed a simple, lightweight, inexpensive afterburner using a pyrophoric fuel. A mixture of Triethylaluminum (TEA) and Trimethylaluminum (TMA) was selected to permit operation at combustion velocities considerably higher than those encountered in regular JP-4 afterburners.
The auto-ignition and high flame speed characteristics of the pyrophoric fuel have speeded the development program in that only a minimum of flame stabilizer and fuel injector development was necessary. Combustion instability phenomena, common in conventionally fueled burners, have not appeared and the reason for the smooth combustion may provide a. new insight into combustion kinetics.
Safe methods of handling the fuel and purging the system have been developed and are explained in the paper.
The new system incorporates a disposable and expendable exhaust jet nozzle which permits operation at altitudes of 35,000 to 65,000 feet at Mach numbers from 0.9 and 1.6. Altitude starting demonstrations at 50,000 feet as well as operational demonstrations throughout the above operating range have been successfully performed. Devices and procedures to permit easy field maintenance have been designed and tested.