Thermodynamic analysis of the chemical regeneration cycle for turboprop engine with ammonia-blended fuel

Amid growing global urgency to reduce carbon emissions, carbon neutrality in aviation has emerged as an international priority. To address this challenge, this study innovatively proposes an ammonia-blended turboprop engine with a chemical regeneration cycle. By integrating the ammonia cracker and regenerator into a unified structure, the system simultaneously achieves waste heat recovery from exhaust gases and ammonia cracking for hydrogen production. The generated hydrogen is then introduced into the combustor, significantly enhancing fuel combustion efficiency and engine cycle efficiency. To evaluate the thermodynamic performance of this system, a comprehensive engine cycle performance analysis model was developed. Results indicate that the ammonia-blended solution reduces carbon emissions by 33.97 % compared to conventional kerosene turboprop engines. Furthermore, the decomposition of ammonia enhances the fuel combustion speed from 1 cm/s to 520 cm/s. Additionally, the study identifies optimal operational ranges for key parameters, including pressure ratio, combustor temperature et al. Notably, the indirect combustion process reduces exergy loss by 5.2 %, which contributes to improving the overall energy utilization level of the engine. In conclusion, this research not only provides an innovative approach but also establishes a systematic theoretical framework and technical implementation pathway for future advancements in green aviation propulsion.