Saint Petersburg State University , 7/9 Universitetskaya Nab. , Saint Petersburg 199034 , Russia.
CNR ISTP , Via Amendola 122/D , Bari 70126 , Italy.
J Phys Chem A. 2019 Dec 12;123(49):10529-10542. doi: 10.1021/acs.jpca.9b08578. Epub 2019 Nov 27.
State-resolved chemical reactions in CO are studied by taking into account excitation of all vibrational modes and preferential reaction mechanisms. The effect of several parameters on the reaction rate coefficients is discussed; it is shown that the nonequilibrium factor in the expression for the rate coefficients of exchange reactions is much less sensitive to the number of accounted vibrational states and model parameters than that of dissociation. On the other hand, the choice of thermal equilibrium Arrhenius law parameters is crucial for the correct prediction of rate coefficients for both reactions. Developed models are implemented to the one-dimensional boundary layer code for coupled state-to-state simulations of nonequilibrium CO flows under Mars entry conditions. Vibrational distributions, mixture composition, flow variables, and heat flux are studied for several kinetic schemes and different models of chemical reactions. Whereas including the exchange reactions weakly affects the flow, switching between the Park and McKenzie sets of parameters results in significant modification of the kinetic mechanisms; for the McKenzie model, recombination near the wall is a dominating reaction, whereas for the Park model, chemical reactions are frozen. Different contributions to the heat flux are evaluated and a satisfactory agreement with experiments is shown.
考虑到所有振动模式的激发和优先反应机制，研究了 CO 中的态分辨化学反应。讨论了几个参数对反应速率系数的影响；结果表明，对于交换反应速率系数表达式中的非平衡因子，其对所考虑的振动态数和模型参数的敏感性远小于离解。另一方面，对于两种反应，正确预测速率系数的关键是选择热平衡 Arrhenius 定律参数。所开发的模型被实现到一维边界层代码中，用于在火星进入条件下进行非平衡 CO 流的态态耦合模拟。对于几种动力学方案和不同的化学反应模型，研究了振动分布、混合物组成、流动变量和热通量。虽然包括交换反应对流动的影响较弱，但在 Park 和 McKenzie 参数集之间切换会导致动力学机制发生显著变化；对于 McKenzie 模型，壁面附近的重组是主要反应，而对于 Park 模型，化学反应被冻结。评估了对热通量的不同贡献，并与实验结果显示出良好的一致性。
