对于O2+N碰撞的高温运输碰撞积分
Wensheng Zhao1,2, Qizhen Hong1, Zoujun Yao3
1State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sciences, 100190 Beijing, China.
The journal of physical chemistry. A
|November 28, 2025
概括
计算了氧分子 (O2) 和原子 (N) 碰撞的碰撞积分. 分析了振动激发对运输特性的影响,在中度不平衡条件下显示了最小的偏差.
科学领域:
- * 分子动力学模拟.
- * * 量子化学 是一个量子化学.
- * 航空动力学 * 空气动力学
背景情况:
- *精确计算运输特性对于建模高温气体流量至关重要.
- * 了解分子振动对碰撞积分的影响对于非平衡条件至关重要.
研究的目的:
- * 计算O2+N碰撞的碰撞积分,使用初始潜在能量表面.
- * 研究O2振动激发在非平衡条件下对传输特性的影响.
- * 评估对碰撞积分的平衡假设和基本状态近似的有效性.
主要方法:
- * 准经典的轨迹分子动力学模拟.
- * 对相关电子状态的高精度初始潜在能量表面.
- * 国家对国家的动力学理论,使用王和乌伦贝克对不弹性贡献的公式.
主要成果:
- * 在高振动温度 (20,000 K) 下,热平均的扩散和粘度碰撞积分显示出高达12%和17%的偏差.
- *对于中度不平衡,偏差小于5% (RRT - TvR ≤ 5000 K),支持平衡假设.
- *使用基本状态值进行振动状态特定碰撞积分的近似推算引入了轻微的错误,简化了计算.
结论:
- * 在O2+N碰撞中适度振动不平衡的情况下,平衡假设是足够的.
- * 对碰撞积分的地面状态近似为实际应用提供了足够的准确性,简化了超音速流动模拟.
- *安装的平均碰撞积分为广泛使用的碰撞模型提供重新参数化的数据.
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