Session: 04-16 Combustor Design IV

Paper Number: 153758

Design and Numerical Investigation of a Swirl-Stabilized Hydrogen Burner for Aero Engine Applications 

In recent years, the potential of hydrogen as an alternative fuel for the decarbonization of the aeronautical sector has been widely recognized in both scientific and industrial combustion communities. Due to its high reactivity and diffusion, the development of new technologies or the improvement of existing ones to safely and efficiently burn hydrogen, presents significant challenges.  Furthermore, nitrogen oxides (NOx) formation is potentially enhanced, becoming one of the primary factors to address.
In this study, a novel 100% hydrogen burner for aero engine applications was designed. The burner realizes a lean, swirl-stabilized flame, achieved with a novel triple coaxial swirlers injector. The innermost channel supplies the fuel, while the two outer channels provide primary and secondary air injections, respectively. The desired injector’s flow split and swirl numbers were firstly individuated by optimizing key objective functions, applying machine learning techniques on the numerical results coming out from Computational Fluid Dynamics (CFD) Reynolds-Averaged Navier-Stokes (RANS) reactive calculations of a parametric pseudo-2D geometry. Indeed, in this early design phase, pseudo-2D RANS calculations allow to run multiple calculations with a reduced computational cost, offering the opportunity to explore several configurations. The most promising one was then down-selected from the set of optimum points before starting the 3D design phase. An iterative procedure exploiting 3D CFD RANS reactive calculations led to the final geometrical parameters and injector design. The burner was completed with the development of an effusion cooling plate for the dome surface, and validated with a 3D CFD reactive Large Eddy Simulation (LES).
The entire workflow was carried out under representative engine operating conditions. Additionally, a detailed LES calculation was run on the burner operated at ambient pressure, in the perspective of the next experimental campaign that will take place at THT Lab of the University of Florence, with results that will be exploited for the test rig design and commissioning.

Presenting Author: Andrea Ballotti DIEF Department of Industrial Engineering, University of Florence

Presenting Author Biography: Andrea graduated in mathematics in 2021 with a thesis on non-Newtonian rheological models. He is currently a PhD student at the Department of Industrial Engineering at the University of Florence. His research focuses on numerical models for hydrogen combustion in aero engines.

Authors:

Andrea Ballotti DIEF Department of Industrial Engineering, University of Florence
Giada Senatori DIEF Department of Industrial Engineering, University of Florence
Sofia Galeotti DIEF Department of Industrial Engineering, University of Florence
Antonio Andreini DIEF Department of Industrial Engineering, University of Florence