过冷大水滴条件下结冰相似准则

虑到中国现有结冰风洞在过冷大水滴(SLD)结冰条件模拟能力方面的局限,发展SLD结冰风洞及其相应的缩比方法迫在眉睫。研究了大水滴运动机理,并依据绕流流场相似、水滴运动和撞击特性相似、结冰过程热力学特性相似原理,提炼出SLD结冰条件下的6种相似缩比准则,利用结冰数值模拟软件FENSAP-ICE对所提相似缩比准则进行筛选与比较,从而基于结冰相似百分比量化判断准则找出给定条件下的最优准则法。结果表明:考虑SLD运动特性的撞击参数与ONERA法相耦合的方法以及撞击参数与Ruff法相耦合的方法的计算结果与实际成冰构型吻合良好；此外,撞击参数与ONERA法相耦合的方法在计算直径为171 μm的SLD时优于其他。 

Icing scaling law at supercooled large droplet conditions

Considering the limits of icing wind tunnels in simulating the SLD(supercooled large droplet) conditions in China, a SLD icing wind tunnel is an urgent realistic problem and its scaled theory needs to be solved. According to the dynamic characteristics and icing mechanism of the supercooled large droplets, six SLD icing scaling laws were proposed with the similarity theory and dimensionless analysis method. Some typical SLD icing conditions were chosen for verifying the SLD scaling law. Based on the FENSAP-ICE software, the ice shapes and other icing parameters were obtained, and also compared for the reliability analysis. Results showed that the coupled approach of impact parameter and ONERA method and the coupled approach of impact parameter and Ruff method had certain superiority and were in good agreement with the reference ice shapes in the test. Besides, the coupled approach of impact parameter and ONERA method was superior to the other methods when the median volumetric diameter was 171 μm.