中文摘要：

采用20步反应机理模拟了H2／空气在内径2mm长20mm的圆管内的预混燃烧．H2／空气预混火焰由壁面向中心传播，呈圆锥形．随着气流向后流动，燃烧区域截面温度曲线由“U”形变为“M”形，后又变为倒“U”形，分别对应壁面加热预混气体的过程，预混燃烧火焰由近壁面向中心传播的过程和燃烧后气体对外散热过程．微燃烧器对外散热量较大，约占总输入热的10％左右，其中燃烧段散热约占5％．辐射散热在壁面散热中占主导地位，占总散热的80％～90％，外壁低辐射系数的材料有利于减少散热和增加燃烧稳定性．对微燃烧而言，燃烧器壁厚增加使燃烧器散热增加，反而不利于降低燃烧器散热．燃烧器入口处壁温与壁面导热系数、壁厚不呈单调变化趋势．在导热系数为3～20w／（m·K）、壁厚为1mm左右时，燃烧器入口处壁温较高，有利于稳定燃烧．

英文摘要：

The combustion of H2/air in the tube with a 2 mm outer diameter was simulated using the 20-step reaction mechanism. The H2/air flame spreads from the wall to the center of the combustor, and the shape of flame is conic. Along the direction in which the gas flows, the shape of the section temperature curves in the combustion area changes from ＂U＂ to ＂M＂, then to ＂handstand-U＂, which are separately corresponding to the gas＇ s heating, the flame＇ s spreading and the heat losing. The heat loss of the microcombustor is very great, about 10% of the input heat. 5% of the heat loss is at the combustion zone, and 80% -90% is radiant heat loss. So the material with low radiation emissivity is beneficial for reducing heat loss and stabilizing the flame. For microcombustion, the heat loss increases with the thickness of the burner wall increasing. The wall temperature of the microcombustor entrance doesn ＇ t change monotonously with the heat conductivity and the thickness of the wall. When the wall heat conductivity is 3 -20 W/（m · K） and the wall thickness is 1 mm, the wall temperature of the combustor entrance is comparatively high, which is favorable for the stabilization of the flame.