Exploration and performance assessment of recuperated rotorcraft powerplant utilizing hydrogen as fuel

Abstract

To address the escalating fuel costs and environmental concerns associated with aviation emissions, this paper presents an integrated multidisciplinary framework to explore the concept of a hydrogen-fueled recuperated rotorcraft powerplant. The overall approach comprises a series of analyses covering rotorcraft flight dynamics, turboshaft engine simulation, hydrogen storage, and recuperator performance. Additionally, design space exploration and weight penalty assessments are conducted within the retrofitted rotorcraft context to evaluate system integration and performance. Comparative studies are performed on various propulsion configurations, including simple and recuperated cycles fueled by kerosene or hydrogen, with a focus on fuel economy and payload capacity. The analysis identifies tank gravimetric efficiency and recuperator thermal effectiveness as critical parameters influencing system weight penalties. Results reveal that the incorporation of recuperator reduces specific fuel consumption (SFC) by 23–44% and 21–41% for kerosene- and hydrogen-fueled engines, respectively. However, at the mission level, hydrogen-powered architectures with recuperators incur energy-to-revenue work ratio (ETRW) penalties exceeding 18% and 21% compared to their kerosene counterparts, at recuperator effectiveness ε_ds of 0.6 and 0.75, respectively. This study establishes the proposed approach as an enabling technology to assess the feasibility of hydrogen as a fuel for rotorcraft powerplants utilizing recuperated engine cycles. The findings contribute to the development of sustainable rotorcraft designs with advanced propulsion configurations.