Application of digital twin technology for combustion and emissions of sustainable aviation fuels

This study investigates the impact of blending Sustainable Aviation Fuels (SAFs) with Jet-A on turboprop engine performance and emissions using a validated physics-based digital twin model. The digital twin of a PT6 engine, achieving over 90 % accuracy, was used to evaluate three SAF types (HEFA, FT-SPK, ATJ) at blending ratios of 5-50 %. The results show that ATJ blends achieved the highest thrust and torque, whereas HEFA blends provided the strongest reductions in CO2, CO, UHC, and soot emissions. FT-SPK offered balanced performance. This approach demonstrates that digital twin modeling can predict the fuel-engine interaction of SAF blends without extensive physical testing, accelerating sustainable propulsion development. The study also highlights current limitations, including the exclusion of NOx formation and the need for future integration of real-time feedback to achieve a fully bidirectional digital twin. NOx emissions were excluded due to model constraints, as their formation is predominantly driven by temperature and turbulence rather than fuel carbon content. All fuel comparisons conducted in this study were performed entirely in the virtual environment of the digital twin model. Validation was carried out only against reference Jet-A engine data, and no experimental validation was performed for the SAF blends.