Session: 04-26 Combustion - Modeling IV

Submission Number: 177836

Numerical and Experimental Investigation of a Laboratory-Scale Hydrogen-Fired FlameSheetTM Burner Operated at Atmospheric Pressure With Full Optical Access 

Hydrogen firing of gas turbines using state-of-the-art Dry Low Emission (DLE) premixed combustion technology offers a clean and efficient pathway towards a resilient and cost-effective low-carbon energy system. However, hydrogen also introduces challenges with greatly increased turbulent burning rate, ultimately leading to significant and yet unresolved challenges in maintaining flame stability and containing NOx emissions. The FlameSheet^TM combustion technology mitigates hydrogen-related flashback issues with a unique U-bend flow pattern and a trapped-vortex flame stabilization strategy, and it has already shown the capability to reliably and cleanly operate with hydrogen-rich fuel mixtures at F-class firing conditions.
In the present work, we numerically and experimentally investigate a lab-scale, cylindrical version of a model FlameSheet^TM burner consisting of a pilot and of a main stage, operated at atmospheric pressure and featuring a simplified geometry with full optical access. The work encompasses a joint research effort combining the numerical simulations, performed by SINTEF, with laboratory experiments, conducted at NTNU. The numerical study consists of high-resolution Large-Eddy Simulation (LES) with realistic turbulence inlet boundary conditions, combined with a detailed depiction of chemical reactions kinetics, and utilizing a Partially-Stirred Reactor (PaSR) model to represent the turbulence-chemistry interaction. The experimental study provides a stability map for the burner main combustion stage, delimited by flashback and lean blowout limits, as a function of the main-stage flame equivalence ratio for constant pilot-stage operating conditions. The LES/PaSR model results are in good agreement with the experimentally observed flame-stability limits for two different main-stage operating conditions. Furthermore, the LES/PaSR datasets provide detailed insights into the turbulent-flow field, the flame shape and stabilization location and, crucially, about the physical mechanism that leads to the occurrence of flashback.

Presenting Author: Hursanay Fyhn SINTEF Energy Research

Presenting Author Biography: Hursanay Fyhn holds a PhD in theoretical and numerical physics from NTNU, Norway, and is a research scientist at SINTEF Energy Research. She works with modelling of turbulent combustion for industrial applications.

Authors:

Hursanay Fyhn SINTEF Energy Research
Ole H. H. Meyer SINTEF Energy Research
Qian Wang Norwegian University of Science and Technology
Nicholas Worth Norwegian University of Science and Technology
Joris Koomen Thomassen Energy
Timothy Dammers Thomassen Energy
Andrea Gruber SINTEF Energy Research