大型商用运输机机翼增升构型水滴撞击特性计算

Numerical simulation of droplet impingement characteristics on a high-lift configuration of a large commercial transport aircraft

基于欧拉-拉格朗日数值模拟框架,发展了一套适合求解三维多体模型水滴撞击特性的计算方法。采用粒子统计与面积比率计算相结合的方式,实现了水滴收集率的高效精确预测。在常规粒径条件下,该方法计算结果与国外标模试验数据吻合良好。应用上述算法,开展了某大型商用运输机增升构型的水滴撞击特性数值模拟研究,计算结果显示:水滴在缝翼背面缝道处出现聚集和轨迹交汇现象,聚集的水滴撞击在缝翼背面后缘,致使当地的水滴收集率出现了严重的激增,这一现象对飞机防冰系统设计提出了新的要求;另外,三维效应对增升构型的撞击特性影响显著,其中主翼下翼面水滴收集率沿展向分布存在较大差异。

An algorithm based on the Euler-Lagrangian simulation framework is developed for analyzing the collection efficiency of a three-dimensional multi-body model.To predict the efficiency of droplet collection efficiently and accurately,the particle statistics method and the area ratio calculation method are integrated in the algorithm.A prior study for a standard model shows that the obtained results agree well with the experimental measurements under the normal droplet size condition.Based on the established algorithm,the droplet impingement characteristics on a high-lift configuration of a large commercial transport aircraft is simulated.The computational results show that the droplet trajectories converge and cross in the gap between the main wing and the slat and then the droplets hit on the trailing edge area of the slat.This phenomenon greatly enhances the local collection efficiency of the slat which is needed to be considered in the design of aircraft anti-icing system.Besides,the collection efficiency distribution on the lower surface of the main wing is different in the span direction,which demonstrates that the droplet impingement characteristics of the high-lift configuration are significantly influenced by the three-dimensional effect.