Detonation Limit Thresholds in H₂/O₂ Rotating Detonation Engine

Abstract

The rotating detonation engine (RDE) is a new engine system using detonation, which may provide a higher performance and smaller and simpler design in comparison with the pulse detonation engine (PDE) and other traditional engines. However the research on RDE stands just at the first step now. The authors perform a numerical analysis to understand about RDE in terms of features of rotating detonation and its propagation limit. The lower threshold pressure of detonation limit was 2.6 MPa and the upper threshold pressure of detonation limit was 7.1 MPa. The engine performance analysis shows that the maximum mixture based specific impulse (I _spm ) was about 440 s, which is comparable with that of the present typical rocket engine.

Keywords:

• Kelvin-Helmholtz instability
• Rotating detonation engine
• Specific impulse

ACKNOWLEDGMENTS

The authors wish to thank Japan Aerospace Exploration Agency (JAXA) supercomputer system for calculations. This research was supported by KAKENHI (21360420).

Notes

p ₀ = manifold pressure; p ₁ = inlet pressure; p ₂ = chamber wall pressure; p′ = supersonic nozzle exit pressure; p″ = subsonic nozzle exit pressure.

p _exit  = exit pressure; p _∞ = ambient pressure; p _out  = outlet pressure.

ρ = density of the gas; u = flow velocity axial.

m _f  = mass of fuel; m _m  = mass of mixture; g = gravity.