无人机红外辐射特性计算与分析

Calculation and analysis on infrared radiation characteristics of UAV

将高精度的CFD技术和红外离散传递法相结合,建立了一套基于纳维-斯托克斯(N-S)方程和光谱辐射强度方程相结合的无人机红外辐射的数值模拟方法。采用CFD方法开展了某无人机蒙皮气动加热性能、发动机排气系统的温度和组分摩尔浓度分布计算,结合离散传递法开展红外探测敏感波段下蒙皮、尾喷口和尾喷焰三个主要辐射源的红外信号特性综合分析,研究了不同红外参数变化下全机外形特征、发动机喷管构型和尾喷焰流场分布对红外辐射贡献的影响,获得了一些可以指导无人机红外隐身设计有价值的结论。

A numerical method was developed for predicting the infrared radiation characteristics of UAV by combining a high precision resolution Computational Fluid Dynamics （CFD） technology of Navier-Stokes equations and discrete transfer method of spectral radiation intensity equation. Firstly, the skin aerodynamic heating performance, engine exhausts temperature and species mole fraction distribution of UAV were calculated by CFD method. Then, combining with discrete transfer method, comprehensive analysis of infrared signal characteristics of main radiation source, such as skin, nozzle and plume, were performed under different infrared detecting sensitive bands. As a result, the effects of the UAV geometric features, the engine nozzle configurations and plume flow field distribution on infrared radiation with different parameters were analyzed. Finally, some valuable conclusions for infrared stealth design of UAV were obtained.