Modeling a methane-hydrogen flame using a vortex burner

The article devoted to the development of a mathematical model and the calculation of a methane- hydrogen flame generated by a vortex burner. The combustion products of hydrocarbon fuels, used in energy and transportation facilities, are the main source of greenhouse gas emissions, leading to increased ambient temperatures and global climate change. Therefore, there has been a recent focus on reducing carbon dioxide emissions from aircraft gas turbine engines and industrial gas turbines. The use of methane-hydrogen fuel can significantly reduce CO2 emissions, but it also leads to changes in combustion modes. There is an increase in flame temperature and propagation speed, which can lead to increased NOx emissions and burnout of installation elements. Therefore, when designing combustion devices and chambers, it is important to study the various combustion modes of methane-hydrogen flames in detail. Computational fluid dynamics methods are widely used to solve these problems, but mathematical models of combustion for methane-hydrogen fuels in relation to vortex flames are still not fully developed. To optimize the design and operation of burner devices, it is necessary to conduct complex mathematical modeling of aerodynamic, heat, and mass transfer processes and combustion. This article describes models for these processes, which were justified and selected based on previous research by the authors for different types of flames. It also presents a mathematical model for calculating swirling methane-hydrogen flames using the vortex-resolving large-eddy simulation (LES) model to describe turbulence. Additionally, the article discusses FGM combustion models with a kinetic reaction mechanism developed at the Institute of Chemical Kinetics and Combustion SB RAS, as well as a discrete ordinate radiation transfer model. A comparison of the calculation results with experimental data obtained by the German Aerospace Research and Technology Center (DLR) showed that the selected mathematical models of turbulent aerodynamics, heat and mass transfer, and chemical reaction processes, as well as the calculation algorithms, make it possible to simulate, with sufficient accuracy for engineering practice, the combustion of methanehydrogen mixtures in swirling flows formed by vortex burners, which are widely used in the combustion chambers of gas turbines. The computational resources required for such calculations are reasonably acceptable when using available cluster systems.