环素燃烧的理论动力学研究:热分解行为和H原子抽象
Siyu Cheng1,2, Yinjun Chen1,2, Frederick Nii Ofei Bruce1,2
1National Key Laboratory of Solid Rocket Propulsion, School of Astronautics, Northwestern Polytechnical University, Xi'an 710072, China.
The journal of physical chemistry. A
|May 7, 2025
概括
使用反应分子动力学 (RMD) 研究了环素 (NCH) 燃烧动力学. 在较低的温度下,H抽象反应是关键,为脉冲引爆发动机 (PDEs) 的NCH燃料模型提供信息.
科学领域:
- 化学动力学 化学动力学
- 燃烧科学是一种科学.
- 计算化学是一种计算化学.
背景情况:
- 环 (NCH) 是脉冲引爆发动机 (PDEs) 的一个有前途的能量燃料.
- 准确的动力模型对于预测NCH燃烧行为至关重要.
- 了解NCH分解路径对于其应用至关重要.
研究的目的:
- 为了研究NCH的取决于温度的动态行为.
- 为NCH开发一个详细的动力模型.
- 阐明NCH的初级分解路径和H抽象反应.
主要方法:
- 使用ReaxFF-lg力场进行反应分子动力学 (RMD) 模拟.
- 佳能 (NVT) 集合模拟用于研究温度效应.
- 高级量子化学计算 (QCISD ((T) /cc-pVXZ//MP2/cc-pVXZ//M06-2X/6-311++G ((d,p)) 用于H抽象反应速度.
主要成果:
- 通过C-N键破裂启动NCH分解,随后是C-H裂变和H抽象.
- 在较低的温度下,H-抽象反应更显著.
- 与其他位置相比,Ortho H抽象具有较低的速率系数;轴向和赤道H抽象表现出类似的反应性.
结论:
- 该研究为NCH提供了关键的动力学参数和热力学数据.
- 这些数据以阿雷尼乌斯和NASA多项式格式呈现,涵盖298.152000 K.
- 这些发现有助于开发NCH在燃烧应用中的精确动力机制,特别是对于PDEs.
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