Ammonia as a carbon-free fuel has great potentiality to be utilized in power generation sectors such as micro gas turbines (MGT) to mitigate carbon dioxide emission from combustion systems. It is also easy to store and transport at room temperature compared to hydrogen, and in liquid form has equal volumetric energy density to liquid hydrogen. However, some challenges regarding its NO_x pollution and flame stabilization inhibit its usage in these areas which requires further studies. In the present study, thermal performance and NO_x emission of an MGT combustor fueled with ammonia-natural gas blends has been analyzed numerically through chemical reactant networks (CRN). The combustor’s inlet conditions are at atmospheric conditions and diffusion flame is stabilized using air swirler. In the first part of the paper, the CRN model has been developed based on empirical and semi-empirical equations. Series of experiments have been carried out to find the required parameters for the CRN model. Also, the results of NO_x emission and temperature distribution have been validated with the experimental results. In the second part, effects of ammonia addition to the natural gas fuel are studied for various ammonia percentages using the CRN. The results show that by increasing ammonia molar percentage in the fuel, NO emission rises dramatically and reaches up to 330 PPM, but after a certain threshold (about 12.5 molar percent of ammonia) further ammonia addition reduces NO emission. Moreover, the overall temperature of the combustor decreases with ammonia addition due to lower LHV (lower heating value) of ammonia relative to natural gas. However, the overall efficiency of the combustor does not change significantly. The results also reveal that most of the NO is produced in the primary and secondary zones of the combustor. NO₂ is mostly created in the secondary zone of the combustor and comprises about 10% of total NO_x emission.

氨作为无碳燃料具有巨大的潜力，可用于发电部门，例如微型燃气轮机（MGT），以减轻燃烧系统的二氧化碳排放。与氢相比，它在室温下也易于储存和运输，并且液态形式的能量密度与液态氢相等。然而，关于其NO _x污染和火焰稳定的一些挑战限制了其在这些领域中的使用，这需要进一步的研究。在本研究中，热性能和NO _x已通过化学反应物网络（CRN）对以氨-天然气混合物为燃料的MGT燃烧器的排放进行了数值分析。燃烧室的入口条件是在大气条件下，并且使用空气旋流器可以稳定扩散火焰。在本文的第一部分中，基于经验和半经验方程式开发了CRN模型。已经进行了一系列实验以找到CRN模型所需的参数。另外，NO _x的结果实验结果验证了排放和温度分布。在第二部分中，使用CRN研究了添加到天然气燃料中的氨对各种氨百分比的影响。结果表明，通过增加燃料中的氨摩尔百分比，NO排放急剧增加并达到330 PPM，但是在达到一定阈值（约12.5摩尔％的氨）之后，进一步添加氨会降低NO排放。此外，由于相对于天然气较低的氨的LHV（较低的热值），燃烧器的总温度随着添加氨而降低。但是，燃烧器的整体效率没有明显变化。该结果还表明，大多数NO是在燃烧器的一级和二级区域产生的。NO ₂大部分在燃烧器和有关的总NO的包含10％的次级区域创建_X排放。