【摘要】 以某轧钢厂步进式加热炉为研究对象，利用Fluent软件对炉内气相流动与燃烧和钢坯加热过程建立数学模型，并开发了用户自定义函数处理钢坯移动。炉膛内气体流动采用Realizable k-ε模型，燃烧过程采用非预混燃烧模型，辐射传热采用DO模型来计算。通过所建立的数学模型，模拟研究了氧气体积分数为21%～35%的助燃气体与燃料燃烧对钢坯加热特性的影响。结果表明，随着氧气浓度的增加，燃烧区的烟气温度逐渐升高，导致钢坯具有更快的升温速率；由于富氧燃烧在燃烧区产生了更均匀的温度场，因此在氧气浓度为35%时，钢坯的黑印温差仅为15 K,比空气工况下的黑印温差低了20 K;当助燃气体中氧气体积分数从21%增加至35%时，钢坯的辐射传热量也随之增加，加热炉热效率从41.1%提高至48.4%。更多还原

【Abstract】 Aimed at a walking beam reheating furnace of a steel rolling mill, a mathematical model for the gas phase flow and combustion in the furnace and the heating process of the slabs was established by Fluent software, and the user-defined function was developed to deal with the movement of the slabs. The Realizable k-ε model was adopted for modeling the gas flow in the furnace, the non-premixed combustion model was used for the combustion process, and the radiative heat transfer adopted the discrete ordinates(DO) model to calculate. Through the established mathematical model, the effects of combustion of flue and the oxidizer with oxygen volume fraction of 21%-35% on heating characteristics of the slabs were simulated. The results show that with the increase of oxygen concentration, the temperature of the flue gas in the combustion zone gradually increases, resulting in a faster heating rate of the slab. Because oxygen-enriched combustion produces a more uniform temperature field in the combustion zone, when the oxygen concentration increases to 35%, the black mark temperature difference of the slab is only 15 K, which is 20 K lower than that under the air condition. When the volume fraction of oxygen in the oxidizer increases from 21% to 35%, the radiant heat transfer of the slabs also increases, and the thermal efficiency of the heating furnace increases from 41.1% to 48.4%.更多还原