Large Eddy Simulations (LES) with the Conditional Moment Closure (CMC) combustion model of swirling ethanol spray flames have been performed in conditions close to blow-off for which a wide database of experimental measurements is available for both flame and spray characterization. The solution of CMC equations exploits a three-dimensional unstructured code with a first order closure for chemical source terms. It is shown that LES/CMC is able to properly capture the flame structure at different conditions and agrees reasonably well with the measurements both in terms of mean flame shape and dynamic behaviour of the flame evaluated in terms of local extinctions and statistics of the lift-off height. Experimental measurements of the overall (liquid plus gaseous) mixture fraction, performed using the Laser-Induced Breakdown Spectroscopy technique, are also included allowing further assessment and validation of the numerical method. The sensitivity of the simulation results to the various boundary conditions is discussed.

中文翻译：

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涡流稳定乙醇喷雾火焰接近吹灭的 LES/CMC 模拟

大涡模拟 (LES) 与旋转乙醇喷雾火焰的条件矩闭合 (CMC) 燃烧模型已在接近吹灭的条件下进行，对于火焰和喷雾特性，可使用广泛的实验测量数据库。CMC 方程的求解利用了具有化学源项一阶闭包的三维非结构化代码。结果表明，LES/CMC 能够正确捕获不同条件下的火焰结构，并且在平均火焰形状和根据局部消光和升力统计评估的火焰动态行为方面与测量结果相当吻合。偏离高度。还包括使用激光诱导击穿光谱技术进行的总体（液体加气体）混合物分数的实验测量，以便进一步评估和验证数值方法。讨论了模拟结果对各种边界条件的敏感性。