Session: 04-26 Combustion - Modeling IV

Submission Number: 177136

Hydrogen-Enriched Methane Combustion in a 3kW Micro Gas Turbine: A CFD Investigation With Experimental Validation 

In the context of carbon-free and decentralized power generation, micro gas turbines (mGTs) represent a promising solution for distributed energy systems, enabling flexible and on-demand power production with reduced environmental impact. Their operational versatility extends to both load modulation and the utilization of alternative and low-carbon fuels. For this purpose, hydrogen is used as an energy carrier, since the absence of carbon in its molecule leads to combustion products free of CO₂. Nevertheless, compared to conventional fuels, hydrogen combustion is characterized by high flame speeds and higher adiabatic flame temperatures; such properties can lead to the occurrence of flame instabilities and flashback.  In this study, combustion performances are studied for small-scale mGTs (3.2 kWe) under various operating conditions. To achieve this goal, CFD represents a powerful tool for the identification and understanding of the critical issues arising under different operating conditions, allowing the adoption of appropriate solutions to ensure stable and efficient combustor operation. Then, a CFD approach based on the RANS framework, employing the k–ω turbulence model coupled with the Eddy Dissipation Concept (EDC) for turbulence–chemistry interaction, was developed and validated against experimental data acquired at the UMARC laboratory of the University of Mons (UMONS).The experimental data were acquired under part-load operating conditions using pure methane and blended fuel mixtures with different volumetric percentages of hydrogen. The comparison focused on emissions, showing good agreement between numerical and experimental results. CFD analyses are carried out at full-load conditions for different fuel compositions, including pure methane and methane–hydrogen blends within the manufacturer’s allowable limits (20% in volume). Finally, additional simulations are performed for hydrogen contents exceeding those limits, considering fuel mixtures with high percentage of hydrogen and pure hydrogen as well, to assess the potential challenges and combustion instabilities arising from increased hydrogen enrichment. The results provide valuable insights into the feasibility and limitations of hydrogen-enriched combustion in micro gas turbines, highlighting both the benefits and technical issues to be addressed for future deployment of low-emission distributed energy systems.

Presenting Author: Vincenzo Ferrara University of Naples Federico II

Presenting Author Biography: Vincenzo Ferrara is a Ph.D. student in Mechanical Engineering at the University of Naples Federico II, Italy. His research focuses on thermoacoustic phenomena in gas turbine combustion chambers using alternative fuels such as hydrogen. He has collaborated with the University of Mons (UMONS) on the study of micro gas turbines aimed at reducing greenhouse gas emissions through numerical and experimental analyses of hydrogen-enriched fuels.

Authors:

Vincenzo Ferrara University of Naples Federico II
Maria Cristina Cameretti University of Naples Federico II
Roberta De Robbio University of Naples Federico II
Alessio Pappa University of Mons
Vincent Thielens University of Mons
Ward De Paepe University of Mons