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Updated: Jan 7, 2026

Combustion Characterization and Model Fuel Development for Micro-tubular Flame-assisted Fuel Cells

Combustion Characterization and Model Fuel Development for Micro-tubular Flame-assisted Fuel Cells

Published on: October 2, 2016

極超音速エンジンの広範なマッハ数範囲における水素・アンモニア協奏燃焼の実現可能性調査

Xin Song¹, Zun Cai², Jianheng Ji¹

¹Advanced propulsion technology laboratory, National University of Defense Technology, Changsha, PR China.

Nature communications

|December 13, 2025

Abstract:

Ammonia shows advantages over hydrocarbon fuels for high-Mach scramjet engines, including superior cooling capacity and carbon-free combustion. However, its operation at lower Mach numbers remains challenging. Here, we successfully demonstrate ammonia-hydrogen ignition at Mach 3 and sustained combustion at Mach 6, confirming the feasibility of hydrogen-ammonia synergistic supersonic combustion. Compared to hydrogen combustion, ammonia addition at low Mach numbers does not alter flame paths but increases flame establishment times by 57.1% upstream and 100% downstream. Both global flame establishment and cavity ignition times are longer under the upstream scheme. At high Mach numbers, two distinct combustion modes are observed. Upstream hydrogen injection ignites more ammonia and produces more intense combustion than downstream injection. These results demonstrate the feasibility of ammonia-fueled scramjets operating across a broad Mach range.

キーワード:

極超音速エンジン水素アンモニア協奏燃焼超音速燃焼実現可能性マッハ数点火持続燃焼航空宇宙工学燃焼科学持続可能燃料

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Combustion Chemistry of Fuels: Quantitative Speciation Data Obtained from an Atmospheric High-temperature Flow Reactor with Coupled Molecular-beam Mass Spectrometer

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