Oxidation of Levitated exo-Tetrahydrodicyclopentadiene Droplets Doped with Aluminum Nanoparticles

Advancement of the next generation of air-breathing propulsion systems will require developing novel high-energy fuels by adding high energy-density materials such as aluminum to enhance fuel performance. We present original measurements, obtained by exploiting the ultrasonic levitation technique, to elucidate the oxidation of exo-tetrahydrodicyclopentadiene (JP-10; C10H16) droplets doped with 80 nm-diameter aluminum nanoparticles (Al NPs) in an oxygen-argon atmosphere. The oxidation was monitored by Raman, Fourier-transform infrared (FTIR), and ultraviolet-visible (UV-Vis) spectroscopies together with high-speed optical and IR thermal-imaging cameras. The addition of 0.5 wt % of the Al NPs was critical for ignition under our experimental conditions occurring at 540 +/- 40 K. Diatomic radicals such as OH, CH, C-2, and AlO were observed during the oxidation of the doped JP-10 droplets, thus providing insight into the reactive intermediates. The influence of the Al NPs on the reaction mechanism is discussed.