对氧气解离速率的振动非博尔兹曼效应
Rui Xiong1, Yufeng Han1, Wei Cao1
1High-Speed Aerodynamics Laboratory, Tianjin University, Tianjin, 300072, China. caow@tju.edu.cn.
Physical chemistry chemical physics : PCCP
|July 10, 2023
概括
对解离率的非平衡 (NB) 影响是使用状态对状态 (STS) 方法比率来量化. 这些NB效应主要是依赖于温度的,无论是在adiabatic还是冲击波放松过程中.
科学领域:
- 化学动力学 化学动力学
- 航空热力学是空气热力学.
- 计算流体动力学的流体动力学.
背景情况:
- 分离速率系数受到内部能量不平衡和振动状态分布效应的影响.
- 状态对状态 (STS) 方法准确地计算了考虑到这两种效应的解离率,而单组线性最大 (SGLM) 模型只考虑了内部能量不平衡.
研究的目的:
- 量化非博尔兹曼 (NB) 对解离率系数的影响.
- 为了研究温度对氧放松过程中的NB效应的影响.
- 为了比较adiabatic热化学不平衡和正常冲击放松过程中的NB效应.
主要方法:
- 利用状态对状态 (STS) 方法来模拟氧气放松过程.
- 从STS和SGLM模型中使用解离率系数的比率 (ζ) 来表示NB效应.
- 模拟的零维 (0D) 加热,在700011000 K的冲击后温度下,对附加热化学不平衡和正常冲击放松过程进行模拟.
主要成果:
- NB效应主要由放松期间的温度来决定.
- 在亚底波和冲击波放松过程中,NB效应表现出类似的变化规则和温度依赖性.
- 当两种过程中的特定内部能量相同时,观察到NB效应的定量一致性.
结论:
- 该比率有效地描述了NB对解离率的影响.
- 温度是影响这些非平衡流动中NB效应的关键因素.
- 这些发现支持通过纳入NB效应来改进非平衡模型,特别是显示在亚底波和冲击波场景中类似的NB行为.
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