建立了直套管型自身预热式辐射管的三维传热过程物理数学模型,并采用FLUENT软件对辐射管的温度场进行了数值模拟。结果表明:随着燃料喷射速度的提高和二次空气量的加大,外壁整体温度升高,辐射管的加热能力增强。较长的内衬管可以更好地导流烟气,保护辐射管外壁,增强辐射管表面温度的均匀性。燃料沿轴向喷入时,火焰长度较长,烟气高温区域较大,有利于辐射管温度均匀性的提高。 The physical mathematical model of the three-dimensional heat transfer process of a straight-tube self-heating radiant tube was established and the temperature field of the radiant tube was numerically simulated by FLUENT software. The results show that with the increase of fuel injection speed and secondary air volume, the overall temperature of the outer wall increases and the heating capacity of the radiant tube increases. Long liner tube can better guide the flue gas, protect the outer wall of the radiation tube and enhance the uniformity of the temperature on the surface of the radiation tube. When the fuel is sprayed in the axial direction, the flame length is longer and the high-temperature area of ​​the flue gas is larger, which is favorable for improving the temperature uniformity of the radiation tube.