Rotating Detonation Engine Performance Model for Rocket Applications

A simplified theoretical treatment of rotating detonation engine (RDE) performance is developed for rocket applications with traceability to current combustion technology. In particular, the influence of unsteady chamber conditions on average chamber pressure, thrust, and specific impulse is assessed for hydrogen, methane, and kerosene fuels with oxygen as an oxidizer. Results are presented for space engine and booster engine conditions, and the influence of nozzle design (bell vs aerospike) is assessed. Results indicate that aerospike nozzles are preferred for RDE applications due to the inherent ability to adjust to a range of operating pressures within the cycle. The RDE system tends to optimize at higher equivalence ratios than conventional engines. Transient nozzle performance diminishes cycle benefits from fundamental thermodynamic analyses, but specific impulse benefits as much as 6–8% might be realized for space engine and booster engine applications, respectively.