A computational investigation of three configurations of the Delft Spray in Hot-diluted Co-flow (DSHC) is presented. The selected burner comprises a hollow cone pressure swirl atomiser, injecting an ethanol spray, located in the centre of a hot co-flow generator, with the conditions studied corresponding to Moderate or Intense Low-oxygen Dilution (MILD) combustion. The simulations are performed in the context of Large Eddy Simulation (LES) in combination with a transport equation for the joint probability density function (pdf) of the scalars, solved using the Eulerian stochastic field method. The liquid phase is simulated by the use of a Lagrangian point particle approach, where the sub-grid-scale interactions are modelled with a stochastic approach. Droplet breakup is represented by a simple primary breakup model in combination with a stochastic secondary breakup formulation. The approach requires only a minimal knowledge of the fuel injector and avoids the need to specify droplet size and velocity distributions at the injection point. The method produces satisfactory agreement with the experimental data and the velocity fields of the gas and liquid phase both averaged and ‘size-class by size-class’ are well depicted. Two widely accepted evaporation models, utilising a phase equilibrium assumption, are used to investigate the influence of evaporation on the evolution of the liquid phase and the effects on the flame. An analysis on the dynamics of stabilisation sheds light on the importance of droplet size in the three spray flames; different size droplets play different roles in the stabilisation of the flames.

提出了对热稀释共流（DSHC）中的代尔夫特喷雾的三种构型的计算研究。选择的燃烧器包括一个空心锥形压力旋流雾化器，该雾化器在热同流发生器的中心注入乙醇喷雾，所研究的条件对应于中度或强烈低氧稀释（MILD）燃烧。在大涡模拟（LES）的背景下结合联合概率密度函数的输运方程进行了模拟（pdf），使用欧拉随机场法求解。液相是通过使用拉格朗日点粒子方法模拟的，其中使用随机方法对次网格规模的相互作用进行了建模。液滴的破裂由简单的一次破裂模型与随机的二次破裂公式结合表示。该方法仅需要很少的燃料喷射器知识，并且不需要指定喷射点处的液滴尺寸和速度分布。该方法与实验数据产生令人满意的一致性，并且很好地描绘了平均和“逐级逐级”的气相和液相的速度场。利用相平衡假设，两个被广泛接受的蒸发模型 用于研究蒸发对液相演化的影响以及对火焰的影响。对稳定动力学的分析揭示了在三个喷雾火焰中液滴尺寸的重要性。不同大小的液滴在稳定火焰中起着不同的作用。