Large-eddy simulations (LES) are presented for a lean preheated high pressure jet flame experiment for which detailed in situ data is available, using a finite rate chemistry (FRC) approach in a gas-turbine model combustor at high Karlovitz number. The impact of the different combustion models on the flame stabilization in the simulation is investigated and the predicted carbon monoxide (CO) and nitric oxide (NO _x ) emissions are analyzed. For the FRC approach, the DRM19 reaction mechanism and a new inhouse skeletal mechanism are applied. The more detailed DRM19 mechanism is extended to include OH* species, the new skeletal mechanism includes CO and NO _x reaction paths. An industry relevant tabulated chemistry approach is assessed on the ability to predict this lifted flame, where the flamelet tables are calculated from the detailed GRI-3.0 reaction mechanism. A dynamic thickened flame approach is applied to resolve the flame on the numerical grid including a model for the turbulence chemistry interaction. Adiabatic and non-adiabatic simulations are compared, where the impact of heat losses due to chamber cooling and thermal radiation are considered. Velocities, temperatures, fuel mass fractions and CO and NO _x mass fractions at different axial locations are in good agreement to the experiments when heat losses are considered. The significant flame lift was correctly predicted by the FRC approach with DRM19 chemistry when non-adiabatic boundary conditions were applied. This provides evidence that the flame is stabilized by flame propagation assisted by auto ignition and that ignition-delay times of mixtures composed of fresh and burnt gases need to be captured by the applied models.

提出了用于稀薄预热高压射流火焰实验的大涡模拟（LES），该实验可获得详细的原位数据，这是在燃气轮机模型燃烧器中以高Karlovitz数使用有限速率化学（FRC）方法进行的。在模拟中研究了不同燃烧模型对火焰稳定的影响，并分析了预测的一氧化碳（CO）和一氧化氮（NO _x）排放量。对于FRC方法，应用了DRM19反应机制和新的内部骨骼机制。更详细的DRM19机制已扩展为包括OH *物种，新的骨架机制包括CO和NO _x 反应路径。根据预测该举起火焰的能力，评估了与行业相关的列表化化学方法，其中小火焰表是根据详细的GRI-3.0反应机理计算得出的。应用动态加厚火焰方法来解析数值网格上的火焰，其中包括用于湍流化学相互作用的模型。比较了绝热和非绝热模拟，其中考虑了由于室冷却和热辐射造成的热损失的影响。速度，温度，燃料质量分数以及CO和NO _x 考虑热量损失时，不同轴向位置的质量分数与实验吻合良好。当应用非绝热边界条件时，采用DRM19化学成分的FRC方法可以正确预测明显的火焰升力。这提供了证据，即火焰通过自动点火辅助的火焰传播得以稳定，并且所应用的模型需要捕获由新鲜气体和燃烧气体组成的混合物的点火延迟时间。