Airbreathing rotating detonation wave engine cycle analysis

A cycle analysis model for an airbreathing, rotating detonation wave engine (RDE) is presented. The engine consists of a steady inlet system with an isolator which delivers air into an annular combustor. A detonation wave continuously rotates around the combustor with side relief as the flow expands towards the nozzle. A model for the side relief is used to find the pressure distribution around the combustor. Air and fuel enter the combustor when the rarefaction wave pressure behind the detonation front drops to the inlet supply pressure. To create a stable RDE, the inlet pressure is matched in a convergence process with the average combustor pressure by increasing the annulus channel radial width with respect to the isolator channel. Performance of this engine is considered using several parametric studies and compared with rocket-mode computational results. A hydrogen–air RDE reaches a specific impulse of 3800 s and can reach a flight speed of Mach 5.