Abstract：According to the power requirements of wide-ranged aviation platforms, a new turbine-augmented combined cycle engine which balances acceleration and fuel economy was proposed in this study. The feasibility of achieving high acceleration and high specific impulse performance using a series connected configuration was initially clarified concerning both engine components and working principles. Firstly, wide-ranged performance of turbine-augmented mode and ramjet mode was assessed using the self-developed performance evaluation model. After that, three-dimensional simulations of typical flight conditions were conducted to ensure the accuracy of the self-developed model. Then, based on the calculations, the engine fueled by liquid oxygen (LO2) and liquid methane (LCH4) reached a specific impulse of approximately 800~1 000 s with a maximum specific thrust of 145 s when working with Mach 0 to 3. Besides, when working at ramjet mode with an equivalence ratio of 1.0, a specific impulse of more than 1 300 s was reached in a Ma4 flight condition and more than 1 000 s in Ma6. Secondly, a preliminary demonstration of the two-stage-to-orbit (TSTO) Astro vehicle based on the turbine-augmented combined cycle engine was carried out. The results have shown the previously mentioned engine can manage high-efficiency reusable space transportation missions with its outstanding wide-ranged acceleration performance. The combined cycle engine was also applicable in the propulsion system for wide-range airborne unmanned platforms covering subsonic to hypersonic speeds, enabling autonomous acceleration and ultra-high-speed cruise. Finally, critical technologies for engine manufacturing were sorted out and summarized.
