The Performance of Hydrocarbon Fuels with H2O2 in a Uni-element Combustor

Abstract : A team from Sierra Engineering Inc, (Sierra), AFRL, and Northrop Grumman Corporation (NGC, formally TRW) tested several different hydrocarbon fuels in a uni-element, 1300 pound thrust hydrogen peroxidel hydrocarbon rocket combustor. Tests were conducted with a variety of hydrocarbon fuels, including JP-8, RP-I, JP-10, toluene, quadricyclane and turpentine, as well as several mixtures of these fields. The combustor used decomposed 90% hydrogen peroxide as the oxidizer. The water-cooled combustion chamber included significant fuel film cooling, with the overall mixture ratio (MR) ranging from 3.75 to 7.4. Testing was conducted at a chamber pressure of approximately 800 psia. Figures of merit presented in this paper include characteristic velocity (eta C*) and energy release efficiencies (ERE). Agreement was generally excellent, with eta C* and ERE agreeing to within 1 %. The experimental performance results were compared with theoretical performance computations. The exhaust plume was monitored during the tests with an infrared spectrometer. Results are shown for integrated band intensities, demonstrating the sensitivity of the plume radiance to variation in combustor operating conditions. In several instances, the variations of the plume intensity could be correlated with events occurring within the combustion chamber. However, the plume measurement was more sensitive than the direct measurements of chamber operating condition (such as pressure and temperature measurements).