飞机结冰中水滴撞击特性欧拉法的网格影响分析

Mesh Impact Analysis of Eulerian Method for Droplet Impingement Characteristics Under Aircraft Icing Conditions

过冷水滴撞击特性计算研究是飞机结冰预测与防除冰系统性能分析的基础,欧拉法是过冷水滴运动及撞击特性计算的常用方法之一,分析欧拉法在计算复杂表面水滴运动撞击时的准确性具有重要意义。以NACA 0012翼型、冰风洞风道、S形进气道及三段翼为研究对象,利用欧拉法采用不同网格计算获得了水滴运动及局部水收集系数,结果表明:当水滴运动没有受到上游部件的导流或者遮挡时,欧拉法计算结果具有网格无关性;当水滴运动受到上游部件影响发生轨迹偏转时,欧拉法计算结果具有网格相关性,不同网格计算得到的液态水含量及局部水收集系数不一致,需要进一步考虑水滴运动受到上游效应影响时网格对欧拉法计算结果的影响。

The research of super-cooled water droplet impingement characteristics is the basis of the ice shape prediction and the aircraft anti-icing system performance analysis.The Eulerian method is frequently used to compute the droplet motion and impingement characteristics,so it is significant to analyze the accuracy of the Eulerian method when calculating the droplet impingement on complex surfaces.Taking a NACA 0012 airfoil,an icing wind tunnel,an S-shape duct and a multi-element airfoil as the research objects,the Eulerian method is used with different meshes to obtain the water droplet motion and collection efficiency.The results show that when the water droplet is not deflected or blocked by upstream components,the results obtained by the Eulerian method are slightly affected by the mesh.However,the results calculated by the Eulerian method are mesh-dependent with upstream trajectory deflections,and the liquid water content and collection efficiency calculated using different meshes are inconsistent.The impact of the mesh on the calculation of the Eulerian method needs to be considered when droplets are affected by upstream effects.The findings of this research are beneficial for the accuracy of aircraft icing simulation.