Abstract The objective of this study is to examine various combinations of vibration-chemical coupling models in high-temperature air and oxygen flows behind shock waves. Simulations are carried out in the frame of the state-to-state approach for detailed vibrational and chemical kinetics in the Euler approximation. Great variety of state-resolved models for the rate coefficients of vibrational energy transitions and chemical reactions are assessed and validated against experimental data; among them are first-order perturbation (SSH) and forced harmonic oscillator (FHO) models; well-known Marrone–Treanor dissociation model with parameters either obtained empirically or by fitting quasiclassical trajectory calculations; new models for state-specific Zeldovich reactions. To validate the models, the results of numerical flow simulations are compared with experimental investigations in a wide range of initial mixture compositions and shock wave velocities. Among numerous model variants, a few models providing the best agreement with the experimental data on the vibrational temperature in oxygen flows and measured NO radiation in air flows are recommended for different sets of free stream conditions. The impact of NO excited states produced in Zeldovich reactions is evaluated; it is shown that neglecting the vibrational excitation of NO molecules may lead to significantly underpredicted maximum of NO number density. In the framework of the code performance study, Matlab and Fortran implementations were compared, the most significant bottlenecks procedures were identified by profiling analysis, and remarkable speed-up was achieved by code optimisation.

中文翻译：

---

冲击加热气流的状态到状态模拟中的模型验证和代码分析

摘要 本研究的目的是检验冲击波后高温空气和氧气流中振动-化学耦合模型的各种组合。在 Euler 近似中详细的振动和化学动力学的状态到状态方法的框架中进行模拟。对振动能量转换和化学反应的速率系数的各种状态解析模型进行了评估和验证；其中有一阶微扰（SSH）和强迫谐振子（FHO）模型；著名的 Marrone-Treanor 解离模型，其参数可以是经验获得的，也可以是通过拟合准经典轨迹计算获得的；特定状态的 Zeldovich 反应的新模型。为了验证模型，数值流动模拟的结果与各种初始混合物成分和冲击波速度的实验研究进行了比较。在众多模型变体中，建议为不同的自由流条件集提供与氧气流振动温度和空气流中测量的 NO 辐射的实验数据最一致的一些模型。评估了 Zeldovich 反应中产生的 NO 激发态的影响；结果表明，忽略 NO 分子的振动激发可能会导致 NO 数密度的最大值显着低估。在代码性能研究的框架内，比较了 Matlab 和 Fortran 实现，通过概要分析确定了最重要的瓶颈程序，