【摘要】 为了研究沼气中CO₂含量、进气速度大小以及过量空气系数等对于沼气的全预混燃烧情况的影响,本文介绍了沼气全预混金属纤维燃烧器,建立了二维金属纤维燃烧器物理模型及数学模型。在Fluent中将金属纤维看作是多孔介质区,并模拟各工况的燃烧情况,然后对各种影响因素进行分析。结果表明,过量空气系数为1¹.25范围内沼气的预混燃烧CO、NO_x排放都较低;进口流速增大使得高温区扩大,燃烧温度上升,CO和NO_x减小趋势放缓;随着沼气中CO₂含量的增大,燃烧速率变小,火焰稳定性变低,沼气中CO₂含量接近50%时仍是可燃的。更多还原

【Abstract】 To study how the different factors,including the CO₂ content in biogas,velocity of inlet and excess air coefficient,affect the condition of biogas premixing combustion,the two-dimensional physical and mathematical model of metal fiber burner were established after a new burner was introduced,which combined biogas premixing combustion with metal fiber. The metal fiber zone in the burner was viewed as porous zone in Fluent. Those different factors were analyzed based on the simulation results of Fluent.The simulation results showed that the emission of CO and NO_x was low when the excess air coefficient vibrated between 1 and 1. 25. The increase of velocity could cause the expansion of high temperature region,increased burning temperature,and slower downtrend of CO and NO_x. Both the combustion rate and flame stability decrease with the content increase of CO₂. The biogas is still combustible when the content of CO₂ in biogas reaches about 50%.更多还原