This work investigates whether both HONO and HNO₂ are essential in describing the reactivity for NO₂-doped ignition experiments or if a strategy could be developed that lumps the two isomers into a single species without adversely affecting the model fidelity. First, the possibility of different product branching fractions is considered; temperature- and pressure-dependent rate constants are computed for H and CH₃ addition to the N=O bond in both HONO and HNO₂. These results suggest that addition of a radical to HONO and HNO₂ do indeed have different products, but that the results are not likely to have a significant effect. Next, two different approaches to simplifying the HONO submechanism are considered. In the first, HNO₂ is removed from the mechanism. In the second, HNO₂ is replaced with HONO. These two strategies are implemented in different literature mechanisms and then used to compute ignition delay times for H₂ and CH₄. The results show that removing HNO₂ has a modest effect on the ignition delay time, whereas systematically replacing HNO₂ with HONO decreases the predicted ignition delay by approximately a factor of two. The recommendation is that for larger fuels, both HONO and HNO₂ should be included in the mechanism.

这项工作调查了HONO和HNO ₂在描述掺杂NO _2的点火实验的反应性方面是否必不可少，或者是否可以开发出将两种异构体混为一个物种而不会对模型保真度产生不利影响的策略。首先，考虑了不同的产品分支分数的可能性；对于HONO和HNO _2中的N = O键中的H和CH ₃加成，计算出温度和压力相关的速率常数。这些结果表明，向HONO和HNO ₂中添加了自由基确实有不同的产品，但结果不太可能产生显著作用。接下来，考虑了两种简化HONO子机制的方法。首先，从该机构中去除HNO ₂。在第二个中，将HNO ₂替换为HONO。这两种策略在不同的文献机制中实现，然后用于计算H ₂和CH _4的点火延迟时间。结果表明，除去HNO ₂对点火延迟时间有适度的影响，而系统地用HONO代替HNO ₂会使预测的点火延迟降低大约两倍。建议对于HONO和HNO较大的燃料该机制应包括_2个。