The micro-jet diffusion flame can act as the heat source for the micro power generation systems due to some advantages. The present work investigates the effect of hydrogen addition on the structure and stabilization of micro-jet methane diffusion flame by numerical simulation. The results show that the oval flame becomes more and more circular with the increase of hydrogen addition fraction. The addition of hydrogen remarkably suppresses the increase of the flame height with the inlet velocity. The methane sharply decreases around the outlet of the micro-jet tube due to the high fresh fuel temperature. The intermediate species (e.g., H₂ and CO) increase sharply before the flame front, and they are consumed sharply within the flame front. With the increase of hydrogen addition fraction, the concentration gradients of reactive species increase before the flame front, while the flame temperature decreases. In addition, with the increase of hydrogen addition fraction, the micro-jet flame root shifts toward the tube-wall and downstream direction at the radial and axial directions, respectively, and the addition of hydrogen decreases the anchoring temperature of the micro-jet flame root, which is conductive to improve the flame stabilization. Meanwhile, a large hydrogen addition fraction is detrimental for the flame stabilization in terms of the thermal interaction between the micro-jet flame and tube-wall. However, the positive effects brought by a large hydrogen addition fraction are noticeably larger than the adjunctive negative effects. This study not only provides the guideline for further expanding the operating range of the micro-jet methane diffusion flame but also helps us to gain insights into the mechanism of hydrogen addition on improving the flame stabilization.

由于一些优点，微射流扩散火焰可以用作微发电系统的热源。本工作通过数值模拟研究了加氢对微射流甲烷扩散火焰的结构和稳定性的影响。结果表明，随着氢添加量的增加，椭圆形火焰变得越来越圆。氢的加入显着抑制了火焰高度随入口速度的增加。由于新鲜燃料温度高，甲烷在微型喷射管出口附近急剧减少。中间物种（例如H ₂和CO）在火焰前锋前急剧增加，并且在火焰前锋内急剧消耗。随着氢气添加量的增加，反应物种的浓度梯度在火焰前沿之前增加，而火焰温度降低。另外，随着氢添加比例的增加，微射流火焰根部分别沿径向和轴向向管壁和下游方向移动，并且氢的添加降低了微射流火焰的锚固温度。根，有助于改善火焰稳定性。同时，就微射流火焰与管壁之间的热相互作用而言，大的氢添加分数对于火焰稳定是有害的。然而，较大的氢添加量所带来的正面影响要明显大于附加的负面影响。这项研究不仅为进一步扩大微射流甲烷扩散火焰的工作范围提供了指导，而且还有助于我们深入了解加氢改善火焰稳定性的机理。