Effect of H₂ Addition on Soot Formation of Acetylene Diffusion Flame in O₂/CO₂ and O₂/N₂ Atmospheres

The height, temperature and soot content of acetylene laminar diffusion flame were obtained by twodimensional extinction method. The effects of H₂ addition in O₂/CO₂ and O₂/N₂ atmosphere on soot particles in acetylene laminar diffusion flame were studied. The results show that the addition of H₂ in the two atmospheres has little effect on the height of acetylene flame, but can increase the acetylene flame temperature, and the temperature increases with the increase of H 2 flow. When the flow ratio of H₂ to C₂H₂ is 0.5, the maximum flame temperature increases in O₂/CO₂ and O₂/N₂ atmospheres are 6.1% and 3.1% respectively. The addition of H₂ in the two atmospheres can significantly inhibit the formation of soot in acetylene flame, with the increase of H₂ flow, the soot volume fraction decreases significantly. When the flow ratio of H₂ to C₂H₂ is 0.5, the inhibition is the strongest, and the soot volume fraction decreases by 24.4% and 27.5% in O₂/CO₂ and O₂/N₂ atmospheres respectively.