The turbulent counter-flow flame (TCF) has proven to be a useful benchmark to study turbulence-chemistry interactions, however, the widely observed bulk flow fluctuations and their influence on the flame stability remain unclear. In the present work, premixed TCFs are studied numerically using a Large Eddy Simulation (LES) method. A transported probability density function (pdf) approach is adopted to simulate the sub-grid scale (sgs) turbulence-chemistry interactions. A solution to the joint sgs-pdf evolution equation for each of the relative scalars is obtained by the stochastic fields method. The chemistry is represented using a simplified chemical reaction mechanism containing 15 reaction steps and 19 species. This work compares results with two meshing strategies, with the domain inside nozzles included and excluded respectively. A conditional statistical approach is applied to filter out the large scale motions of the flame. With the use of digital turbulence, the velocity field in the flame region is well reproduced. The processes of local extinction and re-ignition are successfully captured and analysed together with the strain rate field, and local extinctions are found correlated to the turbulent structures in the reactant stream. The predicted probability of localised extinction is in good agreement with the measurements, and the influence of flame stoichiometry are also successfully reproduced. Overall, the current results serve to demonstrate the capability of the LES-pdf method in the study of the premixed opposed jet turbulent flames.

湍流逆流火焰（TCF）已被证明是研究湍流-化学相互作用的有用基准，但是，尚不清楚广泛观察到的整体流波动及其对火焰稳定性的影响。在目前的工作中，使用大涡模拟（LES）方法对预混合的TCF进行了数值研究。采用输运概率密度函数（pdf）方法来模拟子网格规模（sgs）的湍流-化学相互作用。联合sgs-pdf的解决方案通过随机场方法获得每个相对标量的演化方程。化学使用简化的化学反应机理表示，该机理包含15个反应步骤和19种物质。这项工作将结果与两种啮合策略进行了比较，分别包括和不包括喷嘴内的区域。应用条件统计方法来过滤掉火焰的大规模运动。通过使用数字湍流，可以很好地再现火焰区域中的速度场。成功地捕获了局部灭绝和重燃的过程，并与应变率场进行了分析，发现局部灭绝与反应物流中的湍流结构相关。局部灭绝的预测概率与测量结果非常吻合，并且也成功地再现了火焰化学计量的影响。总体而言，当前结果有助于证明LES-pdf方法用于预混对置射流湍流火焰的研究。