面向过冷大水滴适航验证的结冰探测技术研究

Research on Aircraft Icing Detection of Supercooled Large Droplet for Airworthiness Certification

过冷大水滴(Supercooled large droplet,SLD)结冰超出了常规防除冰系统的防护范围,是一种更为严重的结冰情形,极大地影响着飞行安全。在美国联邦航空管理局14 CFR 25.140条款中明确提到为保证飞机在SLD结冰条件下的安全运行,首先且必须要对SLD结冰气象环境进行探测。由于水滴破碎会改变水滴运动轨迹和表面撞击水分布,使水滴撞击极限变小,而水滴飞溅对结冰极限位置影响不大,因此本文通过研究大、小粒径水滴在飞机上收集范围不同的特点,提出一种可以满足SLD结冰适航符合性的结冰探测技术。该结冰探测技术采用常规结冰探测器,根据水滴收集范围将其布置于不同敏感结冰部位,可以实现全剖面飞行的结冰环境探测。

Supercooled large droplet(SLD)icing is beyond of the protection ability of the conventional antiicing system.SLD is a more serious icing environment and could badly affect the flight safety.In order to ensure flight safety in the SLD icing condition,the precondition is that the SLD should be detected explicitly required by the 14 CFR 25.140 of Federal Aeronautics Administration.It is found that the breakup of droplets will change their trajectory and distribution,and reduce the impingement limit on the wing-leading edge,while the splash of droplets has little effect on the impingement limit.Therefore,ice detection technologies satisfying airworthiness compliance of SLD is studied in this paper considering the characteristics of a various range of large and small droplets.Conventional ice detectors with mature technologies are used and are located in the ice sensitive zones according to the collection range of water droplets.It can detect the whole ice environment in the methods above.