Automated kinetic modeling of fluorinated refrigerants

为了改善对流层中氢氟碳化合物（HFC）的分解，即使HFC具有较低的全球变暖潜势（GWP），主要选择具有双键或添加氢的分子。反过来，较高的反应性也会降低氢氟烃的热稳定性，增强分解反应性和可燃性。因此，只有对潜在的点火、热解和燃烧行为有一个良好而详细的了解，才能确保低GWP的HFC的安全使用。为了在广泛的条件下评估这些行为，需要预测工具来节省时间、精力和实验费用，并提供实验无法获得的数据。化学动力学模型是预测工具的基础，用于理解、优化和设计每种HFC候选物的影响。尽管低全球升温潜能值的氢氟碳化物预计将广泛用作灭火剂和制冷剂工质，但关于详细的化学动力学机制和所涉及的关键基本反应的信息有限。为了解决这一缺点，我们将首先预测低GWP的HFC的化学反应过程，然后再添加实验结果，以了解实验中发生的过程，即使它们是不切实际的测量。然后，我们将改进RMG算法，以便在减少模拟时间的情况下生成低GWP的HFC的大型化学动力学模型。最后，我们将使用更精确的燃烧速度和物种分布实验数据来迭代改进生成机制。

To achieve an improved hydrofluorocarbon (HFC) break down in the troposphere, i.e., what allows HFC to have a low Global Warming Potential (GWP), mainly molecules with double bonds or added hydrogens are selected. In turn, the higher reactivity can also reduce the thermal stability of the HFC enhancing the decomposition reactivity and flammability. Consequently, only a good and detailed understanding of the underlying ignition, pyrolysis, and combustion behaviour ensures a safe use of HFC with low GWP. In order to assess these behaviours under a wide range of conditions, predictive tools are required to safe time, effort, and experimental expenses and to provide data unachievable by experiments. Chemical kinetic models are the basis for a predictive tool and are used to understand, optimize, and engineer the impact of each HFC candidate. Despite the expected widespread use of HFC with low GWP as flame suppressants and refrigerant working fluids only limited information is available on detailed chemical kinetic mechanisms and on the key elementary reactions involved. To address this shortcoming we are going to first predict the course of chemical reactions for HFC with low GWP before adding experimental results to understand processes that are occurring in the experiments even if they are impractical to measure. Then, we are going to improve the RMG algorithm to allow for the generation of large chemical kinetic models for HFC with low GWP in reduced simulation times. Finally, we are going to iteratively improve the generated mechanism using more accurate experimental data for burning velocities and species distributions generated within this group project.