Investigation of auto-ignition in turbulent methanol spray flames using Large Eddy Simulation
Investigation of auto-ignition in turbulent methanol spray flames using Large Eddy Simulation
复制标题
DOI：
10.1016/j.combustflame.2013.07.004
复制
发表时间：
2013-12
影响因子：
4.4
通讯作者：
V. N. Prasad;A. Masri;S. Navarro-Martinez;K. Luo
中科院分区：
文献类型：
--
作者：
V. N. Prasad;A. Masri;S. Navarro-Martinez;K. Luo
本文采用大涡模拟（LES）方法，对最近发展起来的甲醇自燃喷雾火焰进行了数值模拟。采用欧拉随机场方法和包含18种反应组分的简化化学反应机理对湍流反应气相进行了数值模拟。一个完全耦合的拉格朗日粒子方法被施加到代表分散相。气相和液滴的统计显示出良好的整体协议与测量，确认液滴分散和蒸发充分代表。比较快照与图像的OH和CH2O从激光诱导荧光（LIF）突出，所采用的方法也能够捕捉到一系列的关键特征，这一复杂的火焰系列。这包括正确的提离行为，OH的形成标志着火焰底部上游自燃核心的开始，以及在贫条件下存在“最具反应性的混合物”。这与实验数据的协议，使在喷雾自燃的机制的探索。
Large Eddy Simulation (LES) of a recently developed series of auto-igniting methanol spray flames in a vitiated coflow are presented in the paper. The Eulerian stochastic field method and a reduced chemical mechanism involving 18 reactive species are employed to characterise the turbulent reactive gas phase. A fully coupled Lagrangian particle method is applied to represent the dispersed phase. The gas phase and droplet statistics show good overall agreement with the measurements, confirming that droplet dispersion and evaporation are adequately represented. Comparison of snapshots with images of OH and CH2O from laser induced fluorescence (LIF) highlight, that the employed methodology is also able to capture a range of key features that characterise this complex flame series. This includes the correct lift-off behaviour, the formation of OH that mark the initiation of auto-ignition kernels upstream of the flame base and the presence of “most reactive mixtures” at lean conditions. This agreement with experimental data enables the exploration of mechanisms of auto-ignition in sprays.