Numerical Investigation of Rotating Detonation Engines

TLDR

Rotating detonation engines are a less‑explored alternative to pulse detonation engines, and their flow fields and parameter effects such as stagnation conditions, chamber length, and fuel mixture remain poorly understood. The study develops a time‑accurate two‑ and three‑dimensional model for RDEs based on algorithms previously applied to PDE simulations. The model is applied to a stoichiometric hydrogen‑air RDE at 10 atm, 300 K stagnation, 1 atm back pressure, with chamber, inlet, and outlet conditions and integrated quantities computed, and additional simulations explore back‑pressure and inlet‑stagnation effects. Specific impulse varies with pressure ratio (3845–5560 s over ratios 5–30) and is 5130 s at 10 atm stagnation/1 atm back pressure, while mass flow and propulsive force depend mainly on inlet stagnation properties.

Abstract

Rotating detonation engines (RDE’s) represent an alternative to the extensively studied pulse detonation engines (PDE’s) for obtaining propulsion from the high efficiency detonation cycle. Since it has received considerably less attention, the general flow-field and effect of parameters such as stagnation conditions, combustion chamber length, and fuel mixture on specific impulse are less well understood than for PDE’s. In this paper we develop a model for doing time-accurate calculations of RDE’s in two and three dimensions, using algorithms that have successfully been used for PDE simulations previously. Results are shown for a stoichiometric hydrogen-air RDE operating at 10 atm, 300 K stagnation premixture conditions and 1 atm back pressure. Conditions within the chamber are described as well as inlet and outlet conditions and integrated quantities such as total mass flow, force, and specific impulse. Further computations examined the role of back pressure and inlet stagnation pressure on performance. It was found that the specific impulse was dependent on pressure ratio, whereas the mass flow and propulsive force were primarily dependent on the stagnation properties of the inlet micro-nozzles. The specific impulse varied from 3845 sec to 5560 sec over a pressure ratio of 5 to 30. The specific impulse for the 10 atm stagnation pressure, 1 atm back pressure was 5130 sec.