Initiation of Orderly Spinning Detonation Waves via Phased Sparking

Thesis (Master's)--University of Washington, 2016-06

A Continuous Rotating Detonation Engine (CRDE) was tested with two unique features. First, the conventional pre-detonator was replaced by a novel detonation wave generator. This generator sequentially fired spark plugs at a speed near the acoustic speed of a reactant gas mixture thereby producing free radicals ready to partake in detonation. The generator produced high speed detonation waves traveling with homogenous direction in gaseous mixtures of H2 and O2. Detonation waves continued to spin in a self-sustained fashion after turning off the wave generator. The number of simultaneous sparks did not influence the number of detonation waves observed. Instead the number of observed detonation waves was a strong function of the mass flow rate of reactants. Second, the fuel and oxidizer were injected radially. To avoid the thrust-area loss of conventional axial injection, all injection holes were oriented along the annulus radially, thereby allowing the high pressure to work over the entire front end area. Furthermore, radial injection modulated the mixing of fuel and oxidizer to adjust the axial location of detonation zones avoiding damage to the wave generator.