Oxyfuel Combustion is a well-known technique to enhance energy efficiency and CO2-emissions compared to conventional air-fired combustion. To not just reduce on-site fuel consumption but eliminate the combustion related CO2-emissions in accordance with the European Green Deal, switching to hydrogen as a fuel is an option, especially for energy intensive and hard to abate industries like steel and glass making. CFD simulation is an established method for quick and cost-efficient investigation of the influence of parameters on processes and identifying an opti-mum parameter set with less complex and expensive experiments. But many of the existing models used in CFD codes are developed and validated for natural gas combustion with air. A literature review was carried out to identify suitable models for oxyfuel combustion.
The present paper gives an overview over the available kinetic mechanisms, the combustion mechanisms and the Weighted-Sum-of-Gray-Gases radiation models applicable for Natural Gas respectively Hydrogen oxyfuel combustion. CFD simula-tions of a 25 kW oxyfuel furnace with selected model combinations were carried out and compared and validated against experimental data collected from the furnace. An efficient and sufficiently accurate modelling approach for both fuels under oxy-fuel conditions is identified which then can be safely used for hard-to-validate simu-lations of industrial processes under oxyfuel conditions.