摘要
NH_(3)燃料是一种具有应用前景的零碳燃料,但点火困难、反应性低及NO_(x)排放高限制了其实际应用。为了精确区分NH_(3)燃烧过程中,由于燃料和氧化剂均含N元素,导致NO_(x)的生成源难以明确区分,且不同燃烧模式下NH_(3)燃料的NO_(x)生成差异显著性,本文基于已有研究的NH_(3)燃烧详细机理,通过一种类似于同位素标记的化学反应机理建立方式,构建了包含N元素标记的化学反应新机理,给出了详细的数学表达;并通过在仅涉及化学反应过程的均相反应器中,比较验证了区分(NH_(3)/N_(2)/O_(2))和不区分(NH_(3)/N_(2)/O_(2))下模拟结果的有效性。研究结果表明:标记后的机理与未标记的机理相比,组分最大摩尔分数和燃烧产物摩尔分数的平均误差在0.1%以内,且组分最大反应速率预测误差低于0.3%,证明了标记方式的有效性;均相反应器模拟结果显示,随着反应温度的升高,NO的生成源逐渐由以NH_(3)为主转向以N_(2)为主,说明NH_(3)燃烧在不同温度下生成NO的还原机理存在差别。
NH_(3)fuel is a promising zero-carbon fuel,but its difficult ignition,low reactivity and high NO_(x)emission limit its practical application.In order to accurately distinguish the source of NO_(x)formation in the NH_(3)combustion process,due to the fact that both fuel and oxidant contain N elements,it is difficult to clearly distinguish the source of NO_(x)formation,and the significant difference of NO_(x)formation in NH_(3)fuel under different combustion modes.Based on the detailed mechanism of NH_(3)combustion,this paper constructs a new chemical reaction mechanism containing N element labeling by a chemical reaction mechanism similar to isotope labeling,and gives a detailed mathematical expression.The effectiveness of the simulation results under distinguishing(NH_(3)/N_(2)/O_(2))and non-distinguishing(NH_(3)/N_(2)/O_(2))was verified by comparison in a homogeneous reactor involving only chemical reaction processes.The results show that compared with the unlabeled mechanism,the average error of the maximum mole fraction of the component and the mole fraction of the combustion product is less than 0.1%,and the prediction error of the maximum reaction rate of the component is less than 0.3%,which proves the effectiveness of the labeling method.The simulation results of homogeneous reactor show that with the increase of reaction temperature,the generation source of NO is gradually shifting from NH_(3)to N_(2)as the main source,indicating that the reduction mechanism of NO generated by NH_(3)combustion at different temperatures is different.
作者
李爽
刘祥涛
李雨钊
司济沧
LI Shuang;LIU Xiangtao;LI Yuzhao;SI Jicang(Marine Engineering College of Dalian Maritime University,Dalian 116000,Liaoning China;College of Engineering,Peking University,Beijing 100871,China)
出处
《电力科技与环保》
2024年第5期495-503,共9页
Electric Power Technology and Environmental Protection
基金
中央高校基本科研业务费专项资金资助项目(3132024218)。
关键词
氨燃烧
氮氧化物
数值模拟
均相反应器
ammonia
combustion
nitrogen oxide
numerical simulation
homogeneous reactor
