Interactions and synergies between aircraft on-board systems and hydrogen turbofans

The intensive research currently being conducted on hydrogen-powered aircraft concepts poses several integrational challenges. Given that the hydrogen is stored in a liquid state on board the aircraft, a comprehensive analysis is necessary to determine the source of energy required to heat the hydrogen for direct combustion in turbofans. Since the engine itself poses a high-power heat source, it seems feasible that its waste heat may be used for hydrogen conditioning. This paper proposes three different hydrogen engine fuel heat management concepts. These comprise a finned flat tube heat exchanger at different positions within the core engine’s gas stream. A fourth option is presented, which postulates the use of hydrogen instead of fan air to cool customer bleed air. The concepts are evaluated at engine and at mission level, employing an enhanced engine resizing and heat exchanger conceptual design methodology. The results propose that in terms of thrust-specific energy consumption and mission block fuel mass, the intercooler concept is the favorable option. This is mainly attributed to a lower aircraft mass and lower air-side pressure losses compared to the other concepts subject to the study. In addition, the engine cycle efficiency benefits from intercooling the core airflow.

Subjects

DDC Class

629.1: Aviation

Options

Interactions and synergies between aircraft on-board systems and hydrogen turbofans