隐身直升机红外辐射与雷达散射特征分析

Calculation and Analysis of Infrared Radiation and RadarScattering Characteristics of Stealth Helicopter

为实现直升机红外/雷达综合隐身,将一体化红外抑制器融入隐身直升机的设计中,通过数值计算得到悬停状态下直升机的温度场、红外辐射特性以及雷达散射特性。结果表明:在一体化红外抑制器引射气流和旋翼下洗气流的作用下,直升机排气混合管和后机身都可以得到很好的冷却;尾桨通流作用下的高温排气对左侧机身的局部加热效应更显著;排气系统与后机身一体化设计方案使得机身可以有效地遮挡高温混合管,所以3~5μm波段总红外辐射主要来源于气体和机身蒙皮;而在8~14μm波段,气体红外辐射可以忽略不计;在3 GHz、6 GHz、10 GHz和15 GHz频率下,隐身直升机周向RCS均值都控制在4 dBsm以下,表明一体化设计方案在降低红外辐射的同时也具备较好的雷达隐身能力。

To achieve the infrared/radar integrated stealth of a helicopter,the integrated infrared suppressor was incorporated into the design of stealth helicopter.Through numerical simulation,the temperature field,infrared radiation characteristics and radar scattering characteristics of stealth helicopter in hover were calculated.Results showed that under the combined effect of the ejected flow of integrated infrared suppressor and downwash airflow,the mixing duct and rear fuselage of stealth helicopter could be effectively cooled.Under the influence of tail rotor airflow,the local heating effect of the high-temperature exhaust on left fuselage was more significant.Due to the integrated design scheme of the exhaust system and rear fuselage,the latter could effectively shield the high-temperature mixing duct,therefore,total infrared radiation in 3~5μm band was mainly from gas and fuselage skin.However,for 8~14μm band,gas infrared radiation could be neglected.At 3 GHz,6 GHz,10 GHz and 15 GHz frequencies,the RCS mean of the stealth helicopter throughout the entire circumference was controlled below 4 dBsm,which indicated that the integrated design scheme could not only reduce infrared radiation but also have good radar stealth capability.