Water Enhanced Turbofan: Improved thermodynamic cycle using hydrogen as fuel

Abstract

Revolutionary developments are needed to drastically reduce emissions of aviation. Two promising approaches are hydrogen combustion and the water enhanced turbofan (WET). Heat exchangers are needed for both concepts. Whereas for hydrogen combustion, it is necessary to bring liquid hydrogen to operating temperature, the WET requires an evaporator for water and a condenser to extract it from the exhaust flow. Although both technologies may contribute to the mitigation of climate impact individually, it makes sense to combine them in the long term. Unfortunately, it is not known to what extent these approaches can be combined but there is potential for synergy. In this work, a hydrogen-fueled WET is compared with a kerosene-fueled WET. The design approach is described and the interaction of both technologies is investigated. While the thrust specific energy consumption is reduced by 2.2 % when switching to hydrogen, it is also possible to reduce the additional water tank mass by 40 %.