On the response of annular injectors to rotating detonation waves

A series of three-dimensional, unsteady simulations have been conducted to illuminate the behavior of annular gaseous injectors that are frequently used in rotating detonation engine combustors. The strength (detonation overpressure history) and number of detonation waves in the combustor are investigated as operational parameters along with the injector design (area ratio and length) to assess the impact on the unsteady response of the injection system to the imposed detonation model. Attenuation of the imposed overpressure and reflection off the assumed mass flow inlet boundary are features that are highlighted. The unsteady flow at the exit of the injector as a result of these interactions is found to fluctuate by + 80 to - 200%. Strong wave attenuation in the near-exit region of the injector is observed, but acoustic perturbations are seen to propagate throughout the injector, which along with the corresponding reflections persist during the transient injection.