Recently, novel experimental evidence of continuous rotating detonations for gaseous H2/O2 propellants with a rotating detonation rocket engine (RDRE) was attained on the 3-inch Air Force Research Laboratory (AFRL) Distribution A RDRE, with the fuel and oxidizer injectors modified for H2/O2 gas propellants. Evident in previous experiments, detonation instabilities arising from upstream deflagration, from recirculation zones, and from insufficient gas mixing challenged resolution of detonation wave behavior from back-end imaging with the available optical equipment. Images were often over-illuminated from both the high amount of deflagration in the plume and the higher density of detonation waves in the annulus coupled with the small detonation cell size for H2/O2 gas propellants. Additionally, conventional optical systems attenuate the ultraviolet (UV) emission range (~308-320 nm wavelength) from the primary combustion species. To overcome these challenges are two methodologies that still utilize optical back-end imaging: (1) CH* chemiluminescence with fuel doping, and (2) OH* chemiluminescence. The first methodology utilizes doping CH4 into the H2/O2 gas mixture at a relatively small concentration of up to 5% by total mass flow rate to leverage CH* chemiluminescence at 409 ± 32 nm wavelength. The second methodology utilizes the combination of an OH* bypass filter for 308–320 nm wavelength to filter other emissions and an intensifier to amplify the detonation wave OH* emission. As of the present research, the first methodology was investigated across a regime of operating conditions, with planned future testing outlined to facilitate comparable data acquisition utilizing the second methodology.
Master of Science in Aerospace Engineering (M.S.A.E.)
College of Engineering and Computer Science
Mechanical and Aerospace Engineering
Aerospace Engineering; Space System Design and Engineering
Length of Campus-only Access
Masters Thesis (Campus-only Access)
Burke, Robert, "Operability and Wave Characterization of Hydrogen and Oxygen fed Rotating Detonation Rocket Engine" (2020). Electronic Theses and Dissertations, 2020-. 334.