The rotation-diffusion dynamic ignition process in a coupled swirler-cavity hyperburner under high-speed and low-temperature extreme conditions

In the tandem turbine-based combined cycle engine's hyperburner, the complex intrusive design is usually employed to achieve ignition and stable combustion under high-speed and low-temperature extreme conditions. This paper proposes a concise, non-intrusive coupled swirler-cavity configuration to supply the fuel with good atomization at the cavity-trapped vortex center, thereby ensuring the formation of the initial flame kernel. Under the guidance of the cavity-trapped vortex, the initial flame kernel grows through a dynamic “rotation-diffusion” mechanism. Compared to previous studies, the present work achieves ignition and stable combustion under higher incoming Mach numbers (Ma = 0.3, 0.4, 0.5) and lower temperatures (T0 = 300 K).