旋翼下洗气流对红外抑制器性能的影响研究

利用地面模拟试验件实验研究了直升机旋翼下洗气流对红外抑制器气动及红外隐身性能的影响。结果表明,旋翼下洗气流对红外抑制器的气动性能、特征温度、红外辐射等都有明显的影响。旋翼下洗气流速度的增加,将造成红外抑制器的引射系数降低,出口气流温度升高,出口气流温度分布均匀度增加,并使整流罩及外套特征温度迅速增加。存在一个最佳旋翼下洗气流速度,使储物仓特征温度最低。最终,使得在模拟悬停状态下,考虑和不考虑旋翼下洗气流相比,3～5μm的平均红外辐射强度大约增加35%。 

Influences of the Downwash Flow from a Helicopter Rotor on the Performances of an Infrared Suppressor

Experimental diagnostic study has been performed,and results show that the downwash flow had remark able impacts on the aerodynamic performances, characteristic temperatures,and infrared radiation.With the increase in the downwash flow velocity,the entrainment coefficient decreased,and the exhaust flow temperature increased,resulting in the rapid increases of the exhausting duct temperature and the suppressor surface temperature.And finally,the downwash flow at hovering condition caused an increase of total infrared radiation between 3～5 μm by about 35%.