Kerosene-H2 blending effects on flame properties in a multi-fuel combustor

Journal article (2025)

Authors

K Dave Flight Performance and Propulsion
Sarah Link Flight Performance and Propulsion
Francesca de De Domenico Flight Performance and Propulsion
FFJ Schrijer Aerodynamics
Fulvio Scarano Aerodynamics
Arvind Rao Flight Performance and Propulsion
Research Group
Flight Performance and Propulsion
More Info
expand_more

Published Date

2025

Language

English

Research Group

Flight Performance and Propulsion

Abstract

In this study, the macroscopic properties of kerosene-H2 blended flames are investigated in a multi-phase, multi-fuel combustor, focusing on the effects of increasing H2 blending fractions. The non-reacting flow field of the swirl-stabilized combustor is characterized using PIV, and macro-structures in the flow and spray-swirl interactions are analyzed. Kerosene atomizers are tested to estimate variations in spray quality across different fuel blends. The changes in the optical properties of the flames are recorded using broadband chemiluminescence imaging while the changes in the acoustic emissions are recorded using a microphone. Results show that H2 addition significantly alters the flame topology, transitioning from a lobed flame for pure kerosene to a single contiguous swirling flame for blended or pure H2 cases. The flame luminosity decreases, with the emission color shifting from bright yellow (pure kerosene case) to dull yellow (multi-fuel cases) to a red-blue hue (pure H2 case). These changes are attributed to variations in fuel distribution, heat release patterns, combustion mode, flame speed, and soot formation tendencies. The acoustic analysis reveals that a strong tonal behavior is observed under pure fuel conditions (prominent peaks at higher harmonics of 150 Hz) while broadband characteristics are exhibited under blended fuel conditions. The overall acoustic emissions in multi-fuel cases are reduced by ~80% compared to pure H2 and ~55% compared to pure kerosene. This study highlights the effects of high levels of H2 blending on flame dynamics and acoustic behavior in a multi-phase, multi-fuel combustor, offering valuable insights for the development of fuel-agnostic combustion systems.