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采用标准k-ε湍流模型、涡耗散湍流燃烧模型、P-1辐射传热模型对二维简化燃烧室燃料甲烷气、沼气、生物质气的燃烧特性进行了数值模拟.通过比较不同截面的燃烧情况,分析燃烧室内的温度分布、NOx质量分数分布、流场结构,研究了不同热值燃料的燃烧特性.结果表明:在入口空气、燃料质量流量相同的条件下,随着燃料热值降低,燃烧温度降低,温度分布更均匀,NOx排放量减少,流动速度降低;适当调节余气系数,能改善燃烧效果,温度分布仍满足高热值燃料燃烧温度高于低热值燃料燃烧温度的规律;在生物燃料混合气中掺入不同热值的可燃成分,可改变混合气的热值,恰当的混合比例能更好地发挥生物燃料的作用.
The combustion characteristics of two-dimensional simplified combustor fuel methane gas, biogas and biomass gas were numerically simulated by standard k-ε turbulence model, eddy-dissipation turbulent combustion model and P-1 radiative heat transfer model. By comparing the different sections Combustion conditions, the combustion chamber temperature distribution, NOx mass fraction distribution and flow field structure were analyzed and the combustion characteristics of different heat value fuels were studied.The results showed that with the same inlet air and fuel mass flow rate, , The combustion temperature is reduced, the temperature distribution is more uniform, the NOx emission is reduced, and the flow rate is reduced. The proper regulation of the residual gas coefficient can improve the combustion effect, and the temperature distribution still meets the law that the high calorific value fuel combustion temperature is higher than the low calorific value fuel combustion temperature. Biodiesel mixed with combustible components of different calorific value, can change the calorific value of the mixture, the appropriate mixing ratio can better play the role of biofuels.