DROPLET COMBUSTION, MICROEXPLOSION, AND SOOTING CHARACTERISTICS OF SEVERAL ENERGETIC LIQUID PROPELLANTS

The combustion characteristics of droplets of four newly synthesized e nergetic fuels, namely, 1) 1,4-dimethyl ester cubane (which is a solid slightly soluble in conventional liquid fuels), 2) dihydrobenzvalene, 3) phenyl azide, and 4) carborane (which are all liquids), were exper imentally identified and quantified. Results show that the gradual con centration and eventual condensation of dimethyl ester cubane dissolve d in benzene can lead to strong droplet microexplosion; that the three liquid fuels all soot profusely, with the sooting propensity, when co mpared with other fuels, being in the following order: JP-10 < benzene approximate to dihydrobenzvalene < phenyl azide < carborane; and that phenyl azide additionally exhibits fast gasification rates, advanced microexplosion events, and sensitivity to halide addition. It is empha sized that a high-energy-density fuel does not automatically imply tha t it is fast burning, and that it must also possess desirable combusti on characteristics, especially minimal sooting formation, before it ca n be considered for use as a jet fuel or jet fuel additive.