摘要
运用计算流体力学(CFD)二维模型研究预混天然气在小尺度空间内燃烧及墙壁的导热系数、外部的热损对燃烧特性的影响。研究表明,墙壁的导热系数和外壁面的热损直接影响着火焰的点燃、稳定及氮氧化物的生成。对于预混气体,仅存在一个很小的流速区间能维持通道内的燃烧。最后分析了轴向及径向的温度梯度对燃烧器的影响,找到了在模拟条件下最佳的热力条件,并以此达到优化小尺寸燃烧器的目的。
A CFD(computational fluid dynamics) two-dimensional model was employed to study the combustion of premixed natural gas in a small-scale space and the impact of wall heat-conductivity factor and outer wall heat loss on the combustion characteristics.The results of the study indicate that the wall heat conductivity factor and the outer-wall heat loss have a direct influence on the ignition and stability of the flame and the formation of NO_x.As for the premixed natural gas there exists only a zone of very small flow velocity,which can maintain combustion in a channel.Finally,the impact of axial and radial temperature gradient on a combustor was analyzed and,an optimum thermodynamic condition under simulated circumstances has been identified,thereby making it possible to achieve the aim of optimizing a small-sized combustor.
出处
《热能动力工程》
EI
CAS
CSCD
北大核心
2006年第1期48-52,共5页
Journal of Engineering for Thermal Energy and Power
基金
北京市传热与能源利用重点实验室开放基金资助项目(05005790200406)
关键词
天然气
小尺度燃烧
燃烧特性
导热
natural gas,small-scale combustion,combustion characteristics,heat conduction
