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arXiv · 2610.30171

Evaporative Cooling and Secondary Combustion in a Liquid-Hydrocarbon Rotating Detonation Combustor with Dual-Purpose Head-End Injection

Yongbin Zhu·Songbai Yao·Wenwu Zhang
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Abstract

The rotating detonation engine (RDE) faces severe thermal protection challenges. This study numerically investigates a head-end dual-purpose injection configuration in which the film-cooling holes act as both fuel and coolant injectors. An Eulerian-Lagrangian framework is employed, in which the turbulence closure, the film-cooling effectiveness prediction, and the droplet evaporation model are validated against experimental benchmarks. The validated framework is then applied to examine the effects of coolant flow rate, atomization quality, and the fuel allocation between the main flow and the cooling system. Beyond a threshold coolant flow rate the wall temperature drops substantially, whereas an excessively low flow rate elevates it by intensifying local deflagration, revealing a competition between evaporative cooling and secondary combustion that is inherent to this dual-purpose configuration. Fine droplets cool effectively but only over a limited distance downstream, and fuel allocated to cooling weakens the detonation wave and reduces thrust. A moderate coolant flow rate combined with fine atomization is therefore recommended.

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Yongbin Zhu, Songbai Yao, Wenwu Zhang. 2026-10-17. Evaporative Cooling and Secondary Combustion in a Liquid-Hydrocarbon Rotating Detonation Combustor with Dual-Purpose Head-End Injection. https://arxiv.org/abs/2610.30171

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