气体燃烧室中热流场与生成NOx 浓度场的数值模拟研究

Numerical simulation of heat flow field and NOx concentration field in gas combustor

对于一种燃气燃烧器,选取合适的燃烧室尺寸进行匹配,进而构成一个完整的计算区域.天然气燃料和助燃空气通过该燃气燃烧器喷入燃烧室实现完整燃烧过程.通过简化燃气燃烧器完成几何建模,使用热流与燃烧分析软件对计算区域进行数值模拟,选用Realizable k-ε湍流模型、ED燃烧模型、DO辐射模型及热力型NOx生成模型,探究过量空气系数α对该燃气燃烧器燃烧过程的影响,得出其温度场及生成NOx浓度场的相关云图及分布情况并进行分析.当过量空气系数α=1.1时,NOx浓度最大.研究结果可为相关研究实验和设计低NOx燃烧器提供参考依据.

For a kind of gas burner,the appropriate size of the combustion chamber is selected to match,and then a complete calculation area was formed.Natural gas fuel and combustion air were injected into the combustion chamber through the gas burner to realize the complete combustion process.By simplifying the gas burner to complete geometric modeling,heat flow and combustion analysis software were used for numerical simulation of the calculation area,and the Realizable k-εturbulence model,ED combustion model,DO radiation model and thermal NOx generation model were selected to explore the influence of excess air coefficientαon the combustion process of the gas burner.The cloud image and distribution of temperature field and NOx concentration field were obtained and analyzed.When the excess air coefficientα=1.1,the NOx concentration reached the maximum.The research results can provide reference for relevant research experiments and design of low NOx burners.