Synergistic heat recovery–dissipation architecture for hydrogen turbofans: Integrated heat current modeling with multi-parameter thermodynamic analysis

Abstract

Hydrogen-fueled aero engines offer a promising path toward decarbonizing aviation, but their adoption is hindered by the dual challenges of safely preheating cryogenic liquid hydrogen (LH₂) and efficiently recovering onboard waste heat. Most studies focus on components or simplified models, overlooking phase-change effects and intermediate-cycle integration. Moreover, conventional mass-flow-based modeling introduces excessive intermediate variables, limiting efficiency and applicability in complex hydrogen turbofan systems. To address these gaps, this study proposes a novel synergistic heat recovery–dissipation architecture for hydrogen turbofan engines, incorporating four functional heat exchangers and a helium-based intermediate cycle. Besides, a novel energy-flow-oriented thermal modeling framework based on the heat current method is developed, coupled with a phase-change LH₂ preheating model. The model is validated against published data, yielding a temperature deviation below 23.15 K. Parametric analyses reveal that increasing turbine inlet temperature enhances heat transfer performance and thrust, while optimal values of bypass ratio (B = 2.4) and helium flow distribution (ϕ = 0.7) maximize thermal efficiency and preheated hydrogen temperature. Additionally, the helium mass flow rate and its distribution ratio provide effective yet saturable control over heat exchanger performance. These results demonstrate the viability of integrating intermediate-cycle systems into hydrogen turbofans and highlight the advantages of energy-flow-based modeling in reducing system complexity while capturing nonlinear thermal behavior. The proposed architecture and methodology provide new insights into the design of advanced thermal management systems and support the development of high-performance, zero-emission aviation propulsion technologies.