在氧混合物中的州对州碰撞积分和运输系数
1St Petersburg University, 7-9 Universitetskaya Embankment, St Petersburg 199034, Russia.
The Journal of chemical physics
|February 23, 2026
概括
准确的运输系数对于高速飞行至关重要. 这项研究揭示了振动激发显著影响碰撞积分和运输特性,特别是在高温下,需要先进的模型进行准确的预测.
科学领域:
- 航空热力学是空气热力学.
- 化学动力学 化学动力学
- 计算流体动力学的流体动力学.
背景情况:
- 准确的运输系数对于建模高速飞行和大气再进入是必不可少的.
- 现有的模型在极端温度和振动激发分子时往往缺乏精度.
研究的目的:
- 计算O2-O和O2-O2系统的振动状态解析的运输碰撞积分.
- 为这些系统提供一个全面的数据集.
- 分析振动激发对传输性能的影响,并评估现有的模型.
主要方法:
- 使用了准经典轨迹方法.
- 采用高精度的初始潜在能量表面.
- 应用了州对州的动力框架.
主要成果:
- 振动刺激显著影响碰撞积分和传输系数,在高温下效应得到放大.
- 碰撞积分在地面和兴奋的振动状态之间变化高达50%.
- 对于旋转放松时间,观察到与帕克模型的偏差.
结论:
- 传统的现象学模型低估了分子主导混合物中10,000K以上的剪切粘度和导热率.
- 这些模型高估了所有温度的体积粘度.
- 该研究提供了高精度数据,并澄清了计算流体动力学模型适用性限制.
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