Recent advancements in Scramjet combustor: technologies, fuel strategies, and performance challenges

Abstract This investigation examines the performance of Hydrogen- and Kerosene-fuelled Scramjet combustors, emphasizing fuel injection strategies and combustion efficiency. Experimental findings and simulation results showed that hydrogen fuel achieved a combustion efficiency of 96 % when running in struts shortened by 45 % with proper modifications. Dual-strut fuel injection systems deliver better performance levels because their efficiency reaches 92 % compared to setups at 65 %. When injecting across the flow or creating cavities, the mixing becomes more efficient because this technique generates powerful vorticity along the streamwise direction and creates recirculation zones that strengthen flame stability and decrease flow pressure. Combustion in recirculation areas reached maximum temperatures exceeding 2950 K, which ensured stable burner operation. Hydrogen combustion during Mach 4.5 operations led to the minimum pressure loss rate and maximum thermal efficiency outcome. The study confirms that hydrogen functions as the best renewable fuel for Scramjet propulsion, which leads to the development of aircraft systems that are both reusable and environmentally beneficial.