Optimizing Multi-Architecture Gas Turbine Design Employing a 3-Stream Joule-Humphrey Cycle for Cleaner Propulsion

Abstract Air traffic regulations and environmental concerns necessitate the development of more efficient engines, driving the exploration of alternative gas turbine operational cycles as Joule-based turbofans approach their theoretical efficiency limits. To address this challenge, a multi-architecture gas turbine-based engine model has been developed. This model accommodates various configurations, ranging from a conventional 2-shaft turbofan engine to a 3-stream reheated, intercooled, and recuperated core. The proposed framework incorporates both a Rotating Detonation Combustion (RDC) based re-heater and controllable turbine cooling, allowing activation and determination of the optimal bleed extraction point. System dynamics are modeled through a mixed-integer non-linear mathematical framework comprising over 350 continuous and binary variables. Eight key design features are included: core mass flow, bypass ratio, third-stream ratio, portion of reheated air, Overall Pressure Ratio (OPR), intercooler area, recuperator area, and air-to-fuel ratio. Weight modifications are considered in the proposed approach, which are estimated via an in-house weight estimator. The architecture’s overall efficiency is maximized using a multi-start, physics-acquainted Branch and Bound (B&B) algorithm. Overall, the presented model demonstrates the ability to generate engine architectures that achieve higher efficiencies than conventional high-bypass-ratio turbofans. Moreover, the integration of the reheating chamber enables the power plant to achieve increased thrust levels for comparable core and secondary flow rates, significantly enhancing propulsive capabilities without a significant weight addition.