热力学数据对1, 3-丁二烯燃烧特性的影响

基于G4方法, 计算了1,^{3-丁二烯框架燃烧反应机理中102个物种的热力学数据, 并考察了振动非谐性、 频率校正因子以及受阻内转动对结果的影响. 结果表明, 考虑振动非谐性或采用不同的频率校正因子, 对热力学数据的影响不大; 考虑内转动后, 对热力学数据有较大影响. 而且考虑内转动后, 得到的热力学数据与实验热力学数据吻合得更好. 用所得热力学数据模拟了1,3-丁二烯的绝热燃烧温度以及点火延迟时间, 结果显示, 要得到可靠的绝热火焰温度, 对小分子(如CO和CO₂等)的热力学数据需要采用实验结果. 将用所得热力学数据模拟得到的点火延迟时间, 与机理本身的热力学数据所得点火延迟时间进行对比, 二者差别显著, 表明所得热力学数据主要通过改变一些反应的逆反应速率常数来影响点火延迟时间. 进一步确定了用所得热力学数据对点火延迟时间有显著影响的一些物种.}

Effects of Thermodynamic Data on Combustion Characters of 1，3-Butadiene

In this work， thermodynamic data for 102 species in a skeletal reaction mechanism for combustion of 1，3-butadiene were calculated based on the G4 method. Effects of anharmonic vibration， scaling factor for frequencies and internal rotations on these thermodynamic data of these species were investigated. The results show that effects of internal rotations are sizeable on thermodynamic data， while the anharmonic effect and different scaling factor for frequencies do not have a much effect on these thermodynamic data. Agreement between available experimental results and the present thermodynamic data will be improved when the internal rotations are considered. Effects of thermodynamic data obtained in this work on adiabatic combustion temperature and ignition delay time of 1，3-butadiene were also studied. The results indicate that experimental thermodynamic data for small molecules such as CO and CO₂ should be adopted to obtain reliable adiabatic combustion temperatures. On the other hand， ignition delay times with the original thermodynamic data diff considerably from those using thermodynamic data obtained in this work. The results indicate that effects of ignition delay times are affected by thermodynamic data through their effect on rate constants of reverse reactions. Furthermore， species whose thermodynamic data has large impact on ignition delay times are also identified. These works will be important in obtaining reliable thermodynamic data and kinetic mechanism for combustion.