摘要
采用计算流体力学方法对二维微细直管内甲烷和空气的预混燃烧进行了数值模拟,研究了燃烧器尺寸、壁面导热系数、对流换热系数、壁面厚度以及粗糙度对于燃烧的影响。模拟结果显示,燃烧器内径的变化、壁面导热系数、对流换热系数和壁面厚度的变化影响了热量在壁面内的传递和流体内径向温度的传递,使得燃料点燃和燃烧稳定性受到影响,甚至导致燃烧停止。壁面粗糙度增加了燃烧器内流体的扰动,增强了流体与壁面和流体内的换热,导致燃烧稳定性受到影响。模拟结果为设计和开发高效稳定的燃烧器提供了参考。
A computational fluid dynamics was employed to calculate the combustion ofpremixed methane-air in the two-dimensional microscale tube. The effects ofmicroburner dimensions, heat conductivity and thickness of wall, external heat losses and wall roughness on combustion characteristics were studied. The results of simulation indicated that combustor dimensions, heat conductivity and thickness of wall, external heat losses affected the axial heat transfer inside the wall, radial heat tranfer in the fluid, fuel ignition and stability flame, further, induce flame extinction. Wall roughness enhanced fluid disorder and heat exchange between fluid and wall, influenced combustion stability. These results offer some references for designing the high efficiency and stability combustor.
出处
《工业加热》
CAS
2008年第3期13-17,共5页
Industrial Heating
关键词
微尺度燃烧
数值模拟
粗糙度
micro-scale
combustion
numerical simulation
roughness
