Session: 04-16 Combustor Design IV

Paper Number: 153328

Aerothermal Design and Optimization of a High Bypass Hydrogen-Powered Annular Combustor for Small Commercial Aircraft at Cruising Conditions 

Commercial aviation accounts for around 3% of worldwide CO₂ emissions, making environmental mitigation a significant concern. However, in addition to CO₂ emissions, the industry confronts the equally formidable task of reducing nitrogen oxide  (NOx). In recent years, hydrogen has shown the potential for clean combustion in aero engines, making it a viable long-term alternative for gas turbines. This project focused on the design, computational fluid dynamics (CFD) simulation, and optimisation of an annular combustion chamber for a hydrogen-powered large bypass turbofan engine, similar to the CFM 56. The goal was to improve fuel efficiency, reduce NOx emissions, and contribute to aviation to achieve net zero emissions by 2050.

The design was initially developed through theoretical dimension calculations, followed by refinement using CFD simulations. These simulations were used to analyse airflow, temperature distribution, velocity profiles, and pressure drops within the combustor.  For the benchmark data, GasTurb simulations provided realistic operating conditions for a cruising aircraft, which were then adjusted according to the literature to optimise fuel efficiency and reduce NOx emissions.

The final results demonstrated a high temperature concentrated in the core and gradual dissipation towards the combustor walls with a turbine inlet temperature of 1550K, which is ideal for cruise conditions in large bypass engines. The overall air-to-fuel ratio has been improved by 11% compared to the present-day combustors. The combustor had been designed for a 6% pressure drop, and analysis confirmed that it was maintained, with the ultimate pressure value matching the GasTurb simulation. Furthermore, adjustments to the hole diameters, cooling holes, and airflow distribution have resulted in a reduction in NOx emissions as compared to similar studies on annular combustors, indicating its potential as an environmentally friendly alternative fuel for gas turbines.

The findings have significant implications for the aviation industry's transition to more sustainable propulsion technologies. The advances established in this study could serve as a foundation for the development of future hydrogen propulsion systems, giving a roadmap for incorporating sustainable solutions into aviation.

Presenting Author: Yash Chougale University of Staffordshire

Presenting Author Biography: I am an Aeronautical Engineering graduate from Staffordshire University, specializing in aerodynamics and aircraft propulsion. My academic journey has equipped me with a strong foundation in mechanics and thermodynamics, as well as practical experience in CAD design through projects like a manual transmission system. During my studies, I developed expertise in Simulink modeling and real-world control systems, focusing on sustainable solutions, including a net-zero emissions approach to aerodynamics and propulsion.
My efforts in engineering were recognized with the IMechE Best Student Award. Additionally, I recently concluded a consultancy role aimed at reducing the carbon footprint of Better Care Services.

Authors:

Yash Chougale University of Staffordshire
Hossein Sheykhpoor University of Staffordshire
Hamidreza Gohari Darabkhani University of Staffordshire