Singly Conditional Source-term Estimation (CSE) is extended to Doubly Conditional Source-term Estimation (DCSE) to simulate three turbulent ethanol spray flames (EtF1, EtF3 and EtF4) for the first time. Reynolds-Averaged Navier Stokes equations are solved with a two-way coupling Eulerian-Lagrangian method to account for the gas-spray interactions. The objective of this work is to compare the performance of CSE and DCSE in simulating flames with varying levels of pre-evaporation leading to different levels of premixing and combustion modes. Tabulated detailed chemistry is included. The gas phase temperature and spray velocity predictions are compared with experimental data and previously published studies. Both CSE and DCSE can capture the temperature trends adequately. However, DCSE clearly improves the mean temperature predictions over CSE and the predicted temperatures are in close agreement with the experimental data. Close to nozzle exit and centreline, CSE and DCSE systematically predict lower temperatures compared to the experiments. Also noticed in other published studies, this may be due to larger experimental errors at this location, combined with modelling assumptions. Further analysis is conducted by examining the mean heat release rate and mean evaporation rate reproduced in CSE and DCSE. DCSE is shown to better capture some features of the complex structure of these flames. The progress variable predictions are consistent with the temperature predictions. The predicted mean droplets velocity is in good agreement with the experimental data at z/D=10 and z/D=20. However, farther downstream, the mean spray velocity was underpredicted for CSE and DCSE. The liquid volume flux is underpredicted near the centreline indicating higher evaporation rates in the simulations compared to the experiments. The predicted Sauter mean diameter also agrees well with the experiments with some discrepancies for the large droplets. Further investigation is needed to improve the currently available evaporation models.

单条件源项估计 (CSE) 扩展到双条件源项估计 (DCSE) 以首次模拟三种湍流乙醇喷雾火焰（EtF1、EtF3 和 EtF4）。Reynolds-Averaged Navier Stokes 方程使用双向耦合 Eulerian-Lagrangian 方法求解，以解释气体-喷雾相互作用。这项工作的目的是比较 CSE 和 DCSE 在模拟具有不同预蒸发水平的火焰时的性能，从而导致不同水平的预混和燃烧模式。包括详细的化学列表。将气相温度和喷雾速度预测与实验数据和先前发表的研究进行比较。CSE 和 DCSE 都可以充分捕捉温度趋势。然而，DCSE 明显改善了对 CSE 的平均温度预测，并且预测温度与实验数据非常一致。靠近喷嘴出口和中心线，CSE 和 DCSE 系统地预测与实验相比较低的温度。在其他已发表的研究中也注意到，这可能是由于该位置的实验误差较大，再加上建模假设。通过检查在 CSE 和 DCSE 中再现的平均热释放率和平均蒸发率进行进一步分析。DCSE 被证明可以更好地捕捉这些火焰复杂结构的一些特征。进度变量预测与温度预测一致。预测的平均液滴速度与 z/D=10 和 z/D=20 的实验数据非常吻合。然而，更远的下游，CSE 和 DCSE 的平均喷雾速度被低估了。中心线附近的液体体积通量被低估，表明与实验相比，模拟中的蒸发率更高。预测的 Sauter 平均直径也与实验非常吻合，但大液滴存在一些差异。需要进一步研究以改进当前可用的蒸发模型。