过冷大水滴动力学特性对结冰影响数值研究

对比常规水滴，过冷大水滴结冰对飞机气动性能和飞行安全具有更大的危害性。在常规水滴结冰过程数值模拟基础上，针对过冷大水滴条件下各种动力学特性及其对成冰过程的影响进行了数值研究。采用结构化网格和中心有限体积法求解 N-S 方程获得空气流场，用拉格朗日法求解水滴流场，基于改进的 Messinger 热力学模型完成结冰过程模拟；对于过冷大水滴，采用泰勒类比理论和水滴碰撞模型，对比分析了水滴动力学特性及其对结冰过程的影响；通过数值模拟获得了水滴 Langmuir D 分布的撞击特性及结冰计算结果，研究了水滴多尺度分布对成冰过程的影响规律。通过一些典型结冰算例的数值模拟，并与参考文献结果及实验数据的对比分析，说明了本文计算方法及计算模型模拟过冷大水滴结冰是可行和正确的。

Numerical investigation of ice accretion effects at supercooled large droplet conditions

The icing with supercooled large droplet can form the complex ice downstream of the deicing boots.Ice accretion due to the supercooled large droplet may result in extremely severe performance degradation to hazard the flight safety.Research objectives in this paper are to understand the ice accretion effects and reveal the formation mechanism of ice at the supercooled large droplet conditions.A numerical solver is developed to investigate the ice accretion,which include the centered finite volume method for solving the N-S equations to get the air flow field, the Lagrangian method for predicting the flow field of droplets,and a revised Messinger model for simulating the thermodynamic process of icing.Considering the supercooled large droplet conditions,the droplet deformation and breakup using Taylor analogy breakup method are inves-tigated.A splashing model is presented to analyze the splashing phenomenon and the droplet impact.For the supercooled large droplets,the effects of droplet diameter distribution on the movement and impingement process are essential for determining the ice shape.Therefore,the size distribution of droplets needs to be considered during icing simulation.The Langmuir D distribution is studied to get the impact characteristics and icing result of multi-scale distribution of large droplets.Using the above methods,ice accretion and icing effects at the supercooled large droplet conditions over the NACA0012 airfoil are simulated.The calculation results are in good agreement with experimental data,indicating that the methods are feasible and effective.