Numerical study of hydrogen enrichment effects in oxy-flame turbulent of three separated jets

Highlights: • The effects of hydrogen addition to oxy-methane flame were numerically investigated. • The use of H₂ improve the homogenization of jets and the reaction between them. • With the addition of H₂ to oxy-combustion, pollutant emissions decreases (CO, CO₂). • Hythane flame affects to the radiative heat flux and increases the maximum temperature. - Abstract: The development of oxy-fuel combustion in a burner with separated jets presents a promising technology ensuring higher thermal efficiency, better flame stability and more safety compared to premixed combustion. This paper presents a numerical investigation of burner of 25 kW power consisting of a central methane and hydrogen jet surrounded by two oxygen jets. This study aims to evaluate the effect of hydrogen on the dynamics, the distribution of temperature, the stability of the flame, the variation of species mass fraction (CO, CO₂…) and the radiative heat flux. Results show that the addition of hydrogen has a considerable effect on the dynamic behaviour and flame temperature. Indeed, using hydrogen increases the temperature maximum, accelerates the fusion of three jets, and favours the mixing between them. Therefore, it ensures the flame stabilization. Moreover, the results show that the mass fraction of CH₄, CO and CO₂ are highly reduced with the addition of hydrogen. Furthermore, adding hydrogen attenuates the radiative heat flux.