通过Ab Initio计算重新评估二乙烯的高温氧化
Asmae Belghiti1, Marwa Mahmoudi1, Laurent Catoire1,2
1Unité de Chimie et des Procédés (UCP), ENSTA Paris, Institut Polytechnique de Paris, 91120 Palaiseau, France.
The journal of physical chemistry. A
|September 9, 2024
概括
这项研究通过使用先进的计算方法来改进乙烯 (DEE) 燃烧的动力模型,以准确预测高温热解和氧化过程中的CO产量. 新的模型成功地对广泛的实验数据进行了验证.
科学领域:
- 燃烧化学 燃烧化学是什么
- 计算化学的计算化学
- 化学动力学 化学动力学
背景情况:
- 现有的动力模型无法准确预测二甲基乙 (DEE) 高温热解和氧化中的一氧化碳 (CO) 生产.
- 准确的动力学建模对于理解和控制涉及DEE的燃烧过程至关重要.
研究的目的:
- 通过ab initio计算,研究二乙烯 (DEE) 的高温热解和氧化化学.
- 为DEE燃烧开发一个改进的动力模型,准确地描述实验观测,特别是CO产生.
主要方法:
- 使用ab initio计算 (B2PLYP-D3/def2-TZVPD和CCSD) 来确定反应物,产物和过渡状态的特性.
- 使用规范过渡状态理论 (CTST) 和ME/RRKM分析计算了温度和压力依赖的速率常数,并结合了道和阻碍转子校正.
- 新的计算数据与现有的C0-C3核心化学和低温DEE子集集集成,以创建一个全面的动力模型.
主要成果:
- 计算的速率常数与实验测量和以前的文献值进行了比较.
- 新开发的动力模型证明了与DEE氧化和热解的广泛实验数据的成功验证.
- 该模型准确地预测了点火延迟时间,物种化数据,二氧化碳配置文件,层状火焰速度,火焰结构和喷气反应堆数据.
结论:
- 该研究提供了对DEE燃烧化学的精细理解,特别是关于CO形成途径.
- 开发的动力模型为DEE高温热解和氧化提供了改进的预测能力.
- 这项工作有助于为以太基燃料开发更准确的燃烧模型.
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