2D-CFD Simulation of a Syngas Burner with Experimental Validation

Biomass-derived syngas is a promising alternative to fossil fuels for various applications, including internal combustion engines for electricity generation and direct combustion for thermal energy. However, numerical modeling of syngas burners is still scarcely addressed in literature compared to more common fuels, posing challenges for the design of high-efficiency combustors with low pollutant emissions. This study presents a two-dimensional computational fluid dynamics (CFD) simulation of a syngas burner, validated against experimental data. The syngas adopted in the combustion tests is produced using a small-scale gasifier prototype fueled by wood pellets. At first, the syngas is premixed with air, then it moves in a cylindrical burner where the key parameters are monitored, including syngas and air volume flow rates, temperature, and syngas composition. Additionally, an emission analyzer is used to measure O₂, CO, NO, and NO₂, concentrations in the exhaust gases. Given the axial symmetry of the problem, a two-dimensional model is developed to save the computational effort. The simulation results are compared to the experimental measurements including burner temperature and emissions. Despite the simplicity and the reduced effort compared to high-fidelity simulations, the 2D model proves to be able to properly predict both temperature inside the burner and emissions at the exhaust. Therefore, it turns out to be a valuable tool to guide the design of syngas burners.