Transient Modeling and Performance Analysis of Hydrogen-Fueled Aero Engines

With the combustor burning hydrogen, as well as the strongly coupled fuel and cooling system, the configuration of a hydrogen-fueled aero engine is more complex than that of a conventional aero engine. The performance, and especially the dynamic behavior of a hydrogen-fueled aero engine, need to be fully understood for engine system design and optimization. In this paper, both the transient modeling and performance analysis of hydrogen-fueled engines are presented. Firstly, the models specific to the hydrogen-fueled engine components and systems, including the hydrogen-fueled combustor, the steam injection system, a simplified model for a quick NOx emission assessment, and the heat exchangers, are developed and then integrated to a conventional engine models. The simulations with both Simulink and Speedgoat-based hardware in the loop system are carried out. Secondly, the performance analysis is performed for a typical turbofan engine configuration, CF6, and for the two hydrogen-fueled engine configurations, ENABLEH2 and HySIITE, which are currently under research and development by the European Union and Pratt & Whitney, respectively. At last, the simulation results demonstrate that the developed transient models can effectively reflect the characteristics of hydrogen burning, heat exchanging, and NOx emission for hydrogen-fueled engines. In most cases, the hydrogen-fueled engines show lower specific fuel consumption, lower turbine entry temperature, and less NOx emissions compared with conventional engines. For example, at max thrust state, the advanced hydrogen-fueled engine can reduce the parameters mentioned above by about 68.5%, 3.7%, and 12.7%, respectively (a mean value of two configurations).