Development of high rep-rate pulse detonation engines based on transient plasma ignition technology

Summary form only given. pulse detonation engines (PDE) are a class of air breathing engines that offer propulsion from sub- to supersonic velocities from a single system. Critical to this technology is the robust and reliable operation at high repetition rates. This forces consideration of a variety of science and engineering challenges to develop systems that rapidly detonate the fuel-air mixture while maintaining reliability and high efficiencies. This paper focuses on recent results on a number of fronts: First, we report on the implementation of transient plasma ignition (TPI) system in an operational PDE test-bed at NPS. We discuss the physics of deflagration-to-detonation transition and the engineering challenges associated with the system resonances and shock-to-electrode interactions at high rep-rate operation. Second, we describe preliminary efforts to understand the role of plasma streamers in modification of the plasma chemistry, fuel cracking, and deflagration-to- detonation transition. TPI ignition relies on high voltage (10´s of kV) ionization of the fuel-oxidizer mixture, but with sufficiently short pulse lengths (typically <100 ns) to avoid the low efficiencies (thermal energy deposition) of arc formation. The importance of field enhancement, cathode/anode surface physics of the oxidizer, circuit impedance effects, energy coupling, and chemical kinetics on TPI are studied via simulation, and compared with experimental data. Both global models and kinetic particle- in-cell results are discussed.