民用飞机风挡表面对流换热系数的校核

Modification Method of Windshield HTC for Civil Aircraft

摘要:

适航条款要求在结冰条件下,应确保风挡表面不能结冰,防止影响飞行员视界。因此应确定结冰条件下具有足够的电加热功率使风挡表面温度高于冰点(零度),而影响加热功率的关键因素是外表面的对流换热系数。为了获得准确的对流换热系数,在低速风洞中测量了不同工况下风挡表面对流换热系数,并利用CFD方法建立了一个仿真风洞模型,计算试验工况下的风挡表面对流换热系数,通过测量值来校核CFD的计算值,获得一个修正方法,最终使用这个修正方法计算获得其他工况下的对流换热系数。

关键词:民用飞机;风挡;对流换热系数;风洞;修正

Abstract:

According to airworthiness standards, the windshield surface should avoid icing to ensure the pilot's visual field. A reasonable heating power should be determined to prevent windshield icing. The convective heat transfer (HTC) is critical factor to affect heating power setting. For obtaining more accurate HTC, a low velocity wind test has been performed in this paper. And a CFD model has been built as same with test condition to calculate HTC. Comparing and analysis have also been done for finding a reasonable HTC modification method. In theend, the modification method has been used for the other cases.

Key words:civil aircraft; windshield; HTC; wind tunnel test; modification