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提出了一种三维霜冰结冰的数值模拟方法。基于欧拉-拉格朗日法计算空气-水滴两相流流场,获得了表面水滴撞击特性以及撞击量,求解质量守恒和能量守恒方程获得网格单元内的结冰量,三维霜冰的结冰计算程序采用用户自定义(UDF)编写,FLUENT提供的动网格功能实现了结冰后的网格重构。计算了4°攻角,液态水含量为1 g/m3,水滴直径20μm,结冰时间6 min,温度分别为-19.4°和-28.3°时NACA0012翼型的结冰,并与相关文献结果进行了对比,计算结果与文献实验结果吻合较好,验证了方法的合理性和可靠性。分析了不同的粒径、液态水含量、来流速度等对撞击特性以及结冰的影响,随着粒径、来流速度的增加,水滴收集系数、撞击区和结冰厚度增大,随着液态水含量的增加,水滴收集系数和撞击区是不变的,但是结冰厚度增加。
A three-dimensional numerical simulation method of frost ice icing was proposed. Based on the Eulerian-Lagrangian method, the flow field of air-water droplet two-phase flow was calculated, and the impact of the surface droplet and the impact volume were obtained. The mass conservation and the energy conservation equation were used to obtain the amount of ice in the grid cell. The icing calculation program is written in User-Defined (UDF), and the dynamic meshing provided by FLUENT enables grid reconstruction after icing. The ice accretion of NACA0012 airfoil at 4 ° angle of attack, liquid water content of 1 g / m3, water droplet diameter of 20 μm, freezing time of 6 min and temperatures of -19.4 ° and -28.3 ° was calculated and compared with the related literatures In contrast, the calculated results are in good agreement with the experimental results in the literature, which proves the rationality and reliability of the method. The effects of different particle size, liquid water content and flow velocity on the impact characteristics and icing were analyzed. With the increase of particle size and inflow velocity, the droplet collection coefficient, impact zone and icing thickness increased with the increase of The liquid water content increases, the droplet collection coefficient and the impact zone are constant, but the icing thickness increases.